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Number 32June 1998
International Commission on Stratigraphy
International Union of Geological Sciences
Newsletter of the Subcommission on Permian Stratigraphy
Aktastinian and Baigendzhinian section in the Aktasty hills, southern Urals. Aktyubinsk, Kazakhstan
The Sakmarian stratotype section, Sakmara River basin, southern Urals. Kondurovka, Russia
Table of Contents Notes from the SPS Secretary ......................................................................................................................... 1 Claude Spinosa Chairman’s Notes ............................................................................................................................................. 1 Bruce R. Wardlaw Stratigraphy and Sequence Stratigraphy of Kondurovka and Novogafarovo,
the Potential Sakmarian Boundary Stratotype, Southern Ural Mountains, Russia. .................................... 2
Tamra A. Schiappa and Walter S. Snyder
Conodont-Based Refinement of the Aktastinian - Baigendzhinian (Artinskian) Substage
Boundary at the Aktasty Hills Section, Southern Ural Mountains, Kazakhstan ......................................... 7
D. A. Kerner, V. I. Davydov, W. S. Snyder, and C. Spinosa Permian Stratigraphic Units of the Western Verkhoyansk Mountains and their Correlation .................... 8 Aleksandr G. Klets, Igor V. Budnikov, Ruslan V. Kutygin, and Vitaly S. Grinenko Hindeodus parvus: Advantages and Problems .............................................................................................. 8 Wang Cheng-yuan Permian Brachiopods from the Selong Xishan Section, Southern Xizang (Tibet): Preliminary Assemblages and Stratigraphical Implications ........................................................................ 14 Shuzhong Shen, N.W. Archbold, G.R. Shi and Z.Q. Chen Permian Tetrapod Biochronology ................................................................................................................. 17 Spencer G. Lucas Graphic Correlation Applied to Lower Permian Stratigraphic Sections of the Glass Mountains, West Texas ...................................................................................................................................................... 24 Stephen L. Benoist Graphic Correlation of Upper Carboniferous- Lower Permian Strata of Spitsbergen and the Loppa High, Barents Sea Shelf ............................................................................................................... 32 R. M. Anisimov, V. I. Davydov, and I. Nilsson Carboniferous and Permian Stratigraphy of the Baoshan Block, West Yunnan,
Southwest China ............................................................................................................................................. 38
Wang Xiang-dong, Tetsuo Sugiyama and Katsumi Ueno Announcements .............................................................................................................................................. 41
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Foldout #1
Artinskian Biostratigraphy, Aktasty Hills
Foldout #2
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EXECUTIVE NOTES
Notes from the SPS Secretary
Claude Spinosa
I want to thank all who contributed to the 32nd issue of Permophilesand those who assisted in its preparation. We are indebted to BruceR. Wardlaw and Brian F. Glenister for editorial contributions andto Joan White for coordinating the compilation of this issue. Thenext issue of Permophiles is scheduled for December 15, 1998;readers are encouraged to send contributions for inclusion. Con-tributions should arrive before December 1, 1998. It is best tosubmit manuscripts as attachments to E-mail messages. Pleasesend messages and manuscripts to my e-mail address (see bottomof this note). Please note that this is a new E-mail address; thosewho have been using my old one are asked to discard it and beginusing the new address.
Manuscripts may also be sent on diskettes prepared withWordPerfect or MSWord; printed hard copies should accompanythe diskettes. Word processing files should have no personalizedfonts or other code. Specific and generic terms should be itali-cized. Please refer to recent issues of Permophiles (numbers 30 or31) for reference style, format, etc. Maps and other illustrationsare acceptable in tif, jpeg, bitmap or other electronic picture for-mat. If only hard copies are sent, these must be camera-ready, i.e.,clean copies, ready for publication. Typewritten contributions maybe submitted by mail as clean paper copies; these must arrive wellahead of the deadline as they require greater processing time. Wecan also receive contributions via E-mail, Fax or through FTP.
We are indebted to Marc Durand, Mima Stojanovic, HisayoshiIgo, Henri Fontaine, W. M. Furnish, Manfred Menning, YinHongfu, Jurgen Kullmann, Inger Nilssen, Ernest H. Gilmour,Corrado Venturini and six additional donors who wished to re-main anonymous for contributing a total of $475 to the Permophilespublication fund.
Claude SpinosaSecretary, SPS
Permian Research InstituteDept. of Geosciences
Boise State UniversityBoise, Idaho 83725, USA
fax: 208-385-4061voice: 208-385-1581
Chairman’s Report
Bruce R. Wardlaw
The SPS plans to conduct its formal annual meeting for 1999 atthe XIV International Congress on the Carboniferous and Per-mian (August 17-21, 1999) and for 2000 at the 31st InternationalCongress (August 7-16, 2000) where it will conduct a sympo-sium (1-6, see announcement). However, in preparation for the2000 meeting, in an attempt to complete the subcommission’smandate, there will be several meetings sponsored by the SPS inwhich formal meetings will be held. These include:
The International Conference on Pangea and the Paleozoic-Me-sozoic transition (March 9-11, 1999) in conjunction with the Per-mian-Triassic boundary working group of the Subcommission onTriassic Stratigraphy and the SPS working group on the Lopingian.
The International Field Conference on: The continental Permianof the southern Alps and Sardinia (Italy). Regional reports andgeneral correlations (September 16-25, 1999) in conjunction withthe SPS working group on continental-marine correlation.
This year the SPS held its annual meeting at the International Sym-posium of Upper Permian stratotypes of the Volga Region (July28-August 3, 1998, minutes to be included in the next issue). TheSPS also participated in the Guadalupe Mountains Symposium, asymposium celebrating the 25th anniversary of Guadalupe Moun-tains National Park and presented a poster to the park on theGuadalupian Stratotype.
The Carboniferous-Permian boundary working group completedits task with the publication “Proposal of Aidaralash as GlobalStratotype Section and Point (GSSP) for base of the Permian Sys-tem” in Episodes (v. 21, no. 1). The SPS would like to thank theextraordinary efforts of the past two chairs of the working group,Wu Wangshi and Brian Glenister, for guiding and cajoling thegroup to consensus. The working group members also deserve ahearty thanks for a job well done. The working group is nowofficially disbanded.
Bruce R. WardlawChair, SPS
Chief PaleontologistU.S. Geological Survey
926A National CenterReston, VA, 20192-0001 USA
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Stratigraphy and Sequence Stratigraphy ofKondurovka and Novogafarovo, the PotentialSakmarian Boundary Stratotype, Southern UralMountains, Russia.
Tamra A. Schiappa, Walter S. Snyder
Upper Carboniferous through Lower Permian strata atKondurovka and Novogafarovo, southern Ural Mountains, Rus-sia (Fig. 1) were deposited on a storm dominated, open, outer tomiddle mixed carbonate siliciclastic ramp (Fig. 2) that formed theeastern boundary of the Pre-Uralian Foredeep and Ural sub-basin.Our detailed measurement of these stratigraphic sections andlithostratigraphy build on the work completed by Murchison et al.(1845), Karpinsky (1874), Ruzhencev (1936, 1950, 1951), Rauser-Chernousova (1965) and Chuvashov et al. (1993). The Cisuralianstages will be defined formally in the southern Urals of Russiaand therefore, detailed documentation of the lithostratigraphy andsequence stratigraphy is necessary.
The strata from these sections have been divided into severalmajor facies (Table 1) which represent a middle and outer rampdepositional environment consisting of fine to coarse-grained lime-stones with occasional rudstones and floatstones (Fig. 3 (fold out)).The fine grained micrite (M), silty micrite (sM) and mudstone(MS) facies lack any evidence of scouring which suggests deposi-tion from suspension in an offshore, low energy environment.Wackestone-packstone (WP) facies occur as centimeter to meterscale beds, often irregular in thickness and are comprised of vary-ing amounts of skeletal grains, carbonate mud clasts, micrite andsiliciclastic silt. The bioclasts consist of whole fusulinaceans andother small foraminifera, fragmentary bryozoans, crinoids and
Figure 1. Location map of sections studies within the Pre-UralianForedeep, Southern Ural Mountains, Russsia. Kazakhstan,Novogaforova and Kandurovka Sections are located within the UralSub-basin and Aktasty Hills Section located within the Aqt‘be Sub-basin.
International Commission on Stratigraphy Bureau
Subcommission on Triassic Stratigraphy
STS ChairmanProf. Maurizio GaetaniDip. di Scienze della TerraUniversità di MilanoVia Mangiagalli 3420133 Milano, Italyfax: +39 2 70638261voice: +39 2 [email protected]
STS Secretary GeneralGeoffrey Warrington, STSSecretaryBritish Geological SurveyKingsley Dunham Centre,KeyworthNottingham NG 12 5GGGreat [email protected]
ICS ChairmanProf. Jürgen RemaneInstitut de GéologieUniversité de NeuchâtelRue Emile-Argand,11CH-2007 Neuchâtel,Switzerland
ICS 1st Vice ChairDr. H. Richard Lane6542 AudenHouston, TX 77005, USAvoice: (713) 432-1243fax: (713) 432-0139
ICS Secretary GeneralProf. Olaf MichelsonDept. of Earth SciencesUniversity of AarhusDK-8000 Aarhus C, Denmark
REPORTS
Subcommission on Permian Stratigraphy
SPS ChairmanDr. Bruce R. WardlawU.S. Geological Survey926A National CenterReston, VA 22092-0001, USAfax: 703-648-5420voice: [email protected]
SPS 1st Vice ChairmanProf. Ernst Ya. LevenGeol. Inst. RAS 10917Pyjevskyi per 7Moscow, Russiavoice: [email protected]
SPS 2nd Vice ChairmanDr. C. B. FosterAustralian Geol. Surv. Org.GPO Box 378Canberra 2601, [email protected]
SPS SecretaryProf. Claude SpinosaDept. of GeosciencesBoise State UniversityBoise, Idaho 83725, USAfax: 208-385-4061voice: [email protected]
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TABLE 1KONDUROVKA AND NOVOGAFAROVO LITHOFACIES
FACIES DESCRIPTION
Siliciclastics
MS Siltstone-claystone-mudstone
SS1 Very fine, structureless sandstone, interbedded with siltstone-mudstone.
SS2 Fine sandstone beds; grading apparent in some beds with medium to coarse bases;parallel laminations common in most beds, ripple tops occur abundantly; lenticular bedswith lateral dimensions of a few to 30 meters and thickness of a few centimeters, typically15 to 30 cm, and up to 1.5 meters in amalgamated beds.
SS3 Medium (coarse to fine) sandstone; typically graded and parallel laminations; with rippledtops common, but not ubiquitous; erosive bases with flutes, tool marks, load structures;local hummocky cross stratification.
SS4 Gravelites; coarse-grained to granulite sandstones of very fine pebble conglomerates;erosive bases.
CG1 Polymictic pebble to cobble conglomerate; matrix and clast-supported; disorganized toindistinctly stratified beds; some weakly aligned elongate clasts; local slump structures andchannels; some outsized clasts 1 to 4 m in diameter; poorly cemented. Limestone and wellindurated sandstone clasts predominate, but also include metamorphic, granitic, rhyolite toandesitic volcanic, greenstone clasts. Basal contact is typically scoured into underlyingshelf sandstone successions. Fining upward successions 10 to 100 m thick that maycontain variable thickness of lenticular sandstone.
Carbonates
M Light brown to brown micrite; silt content up to approximately 20%.
WP Fossiliferous wackestone - packstone, fine- to medium-grained with variable amounts of siltand fine sands, fusulinaceans, small foraminfers, bryozoans, crinoids fragments, pelloids,and carbonate mud intraclasts.
G1 Fine-grained fusulinacean grainstone, with bryozoan, crinoid, and brachiopod fragments(allochems), pelloids, carbonate mud intraclasts, and variable amounts of extraclasts.Alignment of grains is visible in most samples. Laminar beds with lateral dimensions of afew centimeters to 0.75 meter in thickness.
WPGe Wackestone-packstone-grainstone event beds (“e”); medium- to coarse-grained, locallygraded and scoured bases with rare flute casts and load structure and rippled tops.Constituents same as WP and G1. Beds vary from a few centimeters to 0.75 meter thick.
RFL Gray black and brown limestone pebble rudstone and floatstone, with minor fossiliferousdebris (fusulinacean, crinoid and bryozoan fragments) and carbonate mud clasts. Fine-grained micrite matrix. Carbonate mud clasts vary in size from 1 mm to several tens of cm,tend to be well-rounded and oblate. Some of the clasts appear to have been bioturbatedand silicified and some contain fusulinacean, small foraminifers and crinoid fragments.Bed varies in thickness from 30 centimeters to several meters.
Modifiers:d = dolomitic; a modifier as appropriate for either siliciclastics/carbonatesm = micritic; applied to siliciclastics with < 50% carbonates/ss = silty/sandy; applied to carbonates with < 50% sand/silta = allochemic; carbonate bioclasts
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minor amounts of brachiopod and cephalopod shell fragments.The WP facies represents deposition on a middle ramp with rela-tively moderate energy conditions (Fig 2). The Wackestone-Packstone-Grainstone event bed (WPGe) facies is similar in char-acter to the WP facies with the addition of grainstone. Thegrainstone varies from fine to coarse and is comprised of bothwhole and fragmentary bioclasts, carbonate mud intraclasts andvariable amounts of extraclasts including siliciclastic detritus. Themixture of the bioclastic material, rounded carbonate mudintraclasts and extraclasts indicate event deposition. The depositstend to be graded and may display horizontal laminations at thetop of the beds. Some alignment of grains can be recognizedresulting from currents, however current direction has not yet beendetermined. This facies tends to occur as packages of strata thatfine upward; overall character of this facies is consistent with ei-ther turbidite or tempestite origins. However, with the lack ofobserved basal lags, hummocky cross stratification and wave ripplelaminations, an accurate and positive distinction between the twodepositional mechanisms (wave generated versus current gener-ated) can not be made (Gawthorpe, 1986; Seilacher, 1982). Be-cause of this a generic term “event bed” is used. The fine-grainedfusulinacean grainstone (G1) consists of varying amounts of frag-mentary and whole bioclasts, rounded carbonate mud clasts andextraclasts. The mixture of well-rounded terrigenous and skeletaldebris suggests deposition from submarine currents with mixingof materials derived from two sources (Gawthorpe, 1986). TheG1 facies could be part of the WPGe facies, however, it may re-flect winnowing by submarine currents and waves without sig-nificant transport. The rudstone and floatstone facies (RFL) areoligomictic and consist of rounded to tabular, slightly silicifiedWP and M carbonate mud clasts varying in size, from one milli-meter to tens of centimeters to meters, within a micritic matrix.The poorly sorted, chaotic matrix-supported fabrics of this faciesare typical characteristics of submarine mass gravity flows. Ourinterpretation is that intraclasts were probably derived from upslopebioturbated hardgrounds formed during a sea level lowstand thatoccurred along a distally sted outer ramp. Above Bed 15 (Fig. 3(fold out)), the remainder of the Sakmarian and lower Aktastinianportion of the section changes from a carbonate rich to siliciclasticdominated system and the facies shift to very fine sandstone (SS1),fine sandstone (SS2), medium-grained sandstone (SS3), gravelite,coarse-grained sandstone (SS4) and micritic siltstone (MS) (Table1). These changes in facies associations are interpreted to be theresult of a change in water depth possibly due to a change in sealevel.
Depositional Environment & Sequence StratigraphyThe Kondurovka and Novogafarovo sequences appear to re-
flect deposition on a storm dominated, open, outer to middle mixedcarbonate siliciclastic ramp which is consistent with the strati-graphic nature of the sections and the biota which is dominated bycrinoids, bryozoans and fusulinaceans. Despite fluctuating sealevels (e.g., Ross and Ross, 1988) there is no evidence of sub-aerial exposure in these sections. Lowstand deposits are recog-nized by a higher frequency of event beds and with the rudstone-floatstone units (RFL) identified as a transgressive systems tract.
The stratification types and facies occurrences are the likelyresult of relative sea level changes, episodic, storm-related pro-cesses and possibly tectonism. Sporadic distribution of event bedsoccur throughout these sections but lack observed sedimentary
structures such as sole marks, hummocky cross stratification andwave ripples, which make reconstruction of sedimentary dynam-ics difficult. The most plausible interpretation is that the eventbeds were storm induced and deposited below storm wave base.The model followed is that on a storm-dominated ramp; nearshorestorm set-up water is compensated by offshore-directed bottomreturn flows (Kreisa and Bambach, 1982, Aigner, 1985; Hobdayand Morton, 1984; Walker, 1984). These bottom currents conse-quently erode storm surge channels through which near shore sedi-ment is funneled offshore and deposited as tempestites (Aigner,1985, Seilacher, 1982). Wind drift currents mix bioclastic andsiliciclastic material into shallow skeletal banks. The offshoredirebottom currents transport the pelmatazoan ossicles, bryozoanfragments, fusulinaceans, carbonate mud clasts and siliciclasticsfrom the nearshore and deposit them as WPGe beds.Silty micrite and micritic siltstone dominated successions are in-terpreted as highstand systems tract deposits. The maximum flood-ing surface (MFS) is associated with condensed successions ofsilty micrites and preservation of abundant ammonoids, conodontsand radiolaria. However, some of the ammonoid bearing units areinterpreted as possible sediment gravity flows resulting from stormrelated processes. Submarine cementation appears to have beenminor and the WPe beds derived from the middle ramp during thehighstand, reflect the uncemented, mud and bioclastic-rich andsiliciclasitic-poor lithofacies. The outer ramp condensed succes-sions are overlain by a regressive sequence and are recognized bya gradual shallowing, culminating in a seaward outbuilding ofmiddle ramp horizons, which include wackestones and packstones.Gradation from silty micrite (sM) to silty-sandy wackestone-packstone (s/ssWP) usually occurs within a stratigraphic thick-ness of a few to 10 meters (for example @ 30 to 40 meters abovesection II & III, Fig. 3). The s/ssWP represent deposition on themiddle ramp and contain crinoid, bryozoan, small foraminiferaand fusulinaceans, carbonate mud clasts and siliciclastic debris.Renewed transgressions are documented by the sudden appear-ance of new silty micrite units.
Throughout the Novogafarovo and Kondurovka sections, pack-ages of event beds are present. These packages of relatively abun-dant beds are interpreted as lowstand systems tracts. The uniqueRFL beds are interpreted as a transgressive systems tract and markthe top of a lowstand systems tract at Kondurovka (90 metersabove base section II & III, Fig. 3) and Novogafarovo. Thesedeposits suggest that, during lowered sea level, the exposed innerramp was weakened by physical and chemical processes. As sealevel began to rise, flooding of the inner ramp saturated these units,causing collapse and accumulation as sediment gravity flows onthe middle ramp (Walker, 1984). The succession that contains theRFL beds at Novogafarovo (550-610 meters above base) andKondurovka (70-90 meters above base, sections II & III, Fig. 3) islaterally extensive, typically 0.5 to a tens of meters thick and 10-30 km long along strike. The RFL beds contain well-rounded tooblate carbonate mud clasts varying in size from 1 mm to sevltens of cm to meters, with minor fossiliferous debris (fusulinacean,crinoid and bryozoan fragments) in a fine-grained micrite matrix.This succession is capped by a floatstone bed that contains WPand M carbonate mud clasts that have been slightly silicified. In-terpretations for the origin of this floatstone bed are that it wasdeposited during the transgressive systems tract as a sediment grav-ity flow during flooding of the inner ramp.
Overall, the strata at Kondurovka and Novogafarovo sections
6
represent deposition on a mixed carbonate-siliciclastic storm-domi-nated ramp during the Late Carboniferous and Early Permian.Lowstand deposits are recognized by an increase in event bed fre-quency. Beds 8 and 10 at Kondurovka (section II & III, IV, Fig. 3)are interpreted as RFL beds representing a transgressive systemtract placing the sequence boundary or sea level lowstand with nosubarial exposure below these units. The sequence stratigraphicframework (i.e., sedimentologic continuity and no unconformity)of Kondurovka and Novogafarovo supports placement of theAsselian-Sakmarian boundary as defined by fusulinaceans belowBed 8.
ReferencesAigner, Thomas, 1985, Storm Depositional Systems: Dynamic
Stratigraphy in Modern and Ancient Shallow-MarineSequences, in Friedman, G. M., Neugebauer, H. J., andSeilacher, (eds.), A., Lecture Notes in Earth Sciences, No.3.,Springer Verlag, 174 p.
Chuvashov, B. I., Chernykh, V. V., Davydov, V. I., and Pnev, P.,1993, Kondurovsky Section, in Chuvashov, B. I.,Chermynkh, V. A., Chernykh, V. A., Kipnin, V. J., Molin, V.A., Ozhgibesov, V. P., and Sofronitsky, P. A., (eds.), PermianSystem: Guides to Geological Excursions in the UralianType Localities, jointly published by Uralian BranchRussian Academy of Sciences, Ekaterinburg, Russia andESRI, Occasional Publications ESRI, University of SouthCarolina, New Series No. 10, pg. 102 - 119.
Gawthorpe, R.L., 1986, Sedimentation during Carbonate Ramp-to-Slope Evolution in a Tectonically Active Area: BowlandBasin (Dinantian), Northern England, Sedimentology, v. 33,pg. 185-206.
Hobway, D.K., and Morton, R.A., 1984, Lower CretaceousShelf Storm Deposits, Northeast Texas, in R.W. Tillman, andC. T. Seimers, (eds.), Siliciclastic Shelf Sediments, SEPMno. 34, p. 205-213.
Karpinsky, A. P., 1874, Geological investigations inOrenburgian area. Notes of Mineralogal Soc. Ser. 2, part 9,p. 212-310.
Kreisa, R. D., and Bambach, R. K., 1982, The Role of StormProcesses in Generating Shell Beds in Paleozoic ShelfEnvironments, in G. Einsele and A. Seilacher, (eds.), Cyclicand Event Stratification, Springer-Verlag, p. 200-201.
Murchison, R., Verneuil, E., Kayserling, A., 1845, The geologyof Russian in Europe and the Ural Mountains, vol. 1, TheGeology, London.
Rauser-Chernousova, D. M., 1965, Foraminifers in theStratotypical Section of the Sakmarian Stage (SakmaraRiver, Southern Ural), Academy of Sciences of the USSR,vol. 135, 80 p.
Ruzhencev, V. E., 1936, Upper Carboniferous and LowerPermian stratigraphy in Orenburgian area: Bulletin ofMoscow Society of Natural History, Geological series, v. 14,no. 3., p. 187-214 (in Russian).
Ruzhenzev, V. E. 1950, Type section and biostratigraphy of theSakmarian stage. Doklady Academy of Sci. of USSR, v. 71,p. 1101-1104.
Ruzhencev, V. E., 1951, Nizhneperinskie ammonity YuzhnogoUrala. I. Ammonity Sakmarskogo yarusa (Lower PermianAmmonoids of the Southern Urals. I. Ammonoids of theSakmarian Stage): Akademiia Nauk SSSR,
Paleontologicheskogo Instituta Trudy, v. 33, 188 pp. (inRussian).
Seilacher, A., 1982, Distinctive Features of Sandy Tempestites,in G. Einsele and A. Seilacher, (eds.), Cyclic and EventStratification, Springer-Verlag, p. 161-174.
Walker, R. G., 1984, Shelf and Shallow Marine Sands, in R.G.Walker ed., Facies Models, 2nd ed., Geosciences of Canada,p.141-170.
Tamra A. SchiappaPermian Research Institute
Geosciences DepartmentBoise State University
1910 University DrBoise ID 83725
Walter S. SnyderPermian Research Institute
Department of GeosciencesBoise State University
1910 University DrBoise ID 83725
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Conodont-Based Refinement of the Aktastinian -Baigendzhinian (Artinskian) Substage Boundary atthe Aktasty Hills Section, Southern Ural Mountains,Kazakhstan
D. A. Kerner, V. I. Davydov,W. S. Snyder, C. Spinosa
Upper Paleozoic strata of the Pre-Uralian foredeep in the south-ern Ural Mountain region of Russia and Kazakhstan comprise thetype area of the Cisuralian Series (Lower Permian), consisting ofAsselian, Sakmarian, Artinskian, and Kungurian stages. Currentstudies in the region will attempt to establish stratotypes and pre-cise chronostratigraphic stage and substage boundaries of theCisuralian based on biostratigraphic and sequence stratigraphicdata. Both serve as powerful tools for correlating Cisuralian stagesworldwide via recognition of widely distributed fauna and eustaticsequence boundaries.The Aktasty Hills section, located near Aqtöbe (formerlyAktyubinsk), Kazakhstan (see location map: Schiappa, this issue,page 2, Fig. 1) consists of 1120 m of Lower Permian marine strataof Upper Asselian through Artinskian (Aktastinian andBaigendzhinian) age. The section is a logical choice to serve asthe stratotype for a modern definition of the base of theBaigendzhinian substage (and concurrently, the top of theAktastinian) because it was employed by V. E. Ruzhencev (1956)for the definition of the two Artinskian substages.Ammonoids, conodonts, and radiolarians are abundantly preservedthroughout the section, and fusulinaceans occur in the lower 175m. Detailed studies of the biostratigraphy and sequence stratigra-phy of the Aktasty Hills section are currently underway by Rus-sian colleagues (Chuvashov, 1996) and members of PRI. Thesestudies could serve as the basis for a proposal to establish theAktasty Hills section as stratotype for the Aktastinian -Baigendzhinian substage boundary of the Artinskian stage. Cur-rent definition of Global Standard Stratotype Section and Point(GSSP), regarding bases of chronostratigraphic units, as set forthby the International Commission on Stratigraphy (Salvador, 1997;Remane, 1996) require them to be established within continuousevolutionary lineages and depositional sequences, i.e., bases cannot be defined at sequence boundaries (unconformities).Lower Permian (Cisuralian) strata at Aktasty Hills were first de-scribed by V. E. Ruzhencev (1951, 1952, 1956).Chronostratigraphic units were defined based on ammonoids, nau-tiloids and fusulinaceans from 8 locations. Substages of theArtinskian stage (Aktastinian/Baigendzhinian) were defined atAktasty Hills based on diverse ammonoid and nautiloid assem-blages at three locations. Data are summarized in Figure 1b (foldout).We remeasured and resampled the section in 1993, 1994 and 1997.Additional ammonoid localities were identified and collected, andthe section was also sampled for conodonts and palynomorphs.Within the Artinskian (based on Ruzhencev’s divisions) 71 con-odont samples were collected and 7 ammonoid locations weresampled. Preliminary biostratigraphic data and stratigraphy aresummarized in the fold out facing this page.New ammonoid and conodont data suggest that the Aktastinian -Baigendzhinian substage boundary be located approximately 220
meters below its present position. The boundary is currently lo-cated at 945 m above the base of the section at the top ofRuzhencev’s Bed 8 which contains primarily Artinskian am-monoids and one Aktastinian form; Paragastrioceras tschernowi.Several additional ammonoid localities containing possibleBaigendzhinian forms such as Metalegoceras klimovi (evolutum?)and Eothinites aktastensis have been sampled below Ruzhencev’sBed 8 at 856 and 867 meters above base. In addition,neostreptognathotid conodonts, possibly Neostreptognathoduspequopensis, exist from a sample from 729 meters above base.Conodont zonations by Kozur (1995) and Ritter (1986) indicateN. pequopensis ranges throughout the Baigendzhinian.
ReferencesChuvashov, B., 1996, Report from the working group of the
Asselian, Sakmarian and Artinskian stratotypes, Permophiles,no. 29, p. 2-3.
Kozur, H., 1995, Permian conodont zonation and its importancefor the Permian stratigraphic standard scale, Festschrift zum60, Geburtstag von Helfried Mostler, Geol. Palaont. Mitt.Innsbruck, ISSN 0378-6870. Bd.20.S. 165-205
Remane, J., M.G. Bassett, J.W. Cowie, K.H. Gohrbandt, H.R. Lane,O. Michelsen and Wang Naiwen, 1996, Guidelines for the es-tablishment of global chronostratigraphic standards by the In-ternational Commission on Stratigraphy (ICS) (Revised),Permophiles, no. 29, p. 25-30.
Ritter, S.M., 1986, Taxonomic revision and phylogeny of post-Early Permian crisis bisselli-whitei zone conodonts with com-ments on Late Paleozoic diversity.- Geologica etPalaeontologica, 20, 139-165.
Ruzhencev,V. E., 1951. Lower Permian ammonoids of SouthernUrals. I. Ammonoids of Sakmarian stage. Transactions ofPaleontol. Inst.; Ac. Sci. USSR, 33, 1-188.
Ruzhencev,V. E., 1952. Biostratigraphy of Sakmarian Stagein Aktiubinsk province, Kazakhstan SSR. Transactionsof Paleontol. Inst.; Ac. Sci. USSR, 42, 1-87.
Ruzhencev,V. E. 1956. Lower Permian ammonoids of SouthernUrals. Ammonoids of Artinskian Stage. Transactions ofPaleontol.; Inst.; Ac. Sci. USSR, 60: 1-274.
Salvador, A., 1997, Proposed new chronostratigraphic units forthe Upper Permian, Permophiles, no. 30, p. 3-4.
D. A Kerner.V. I. DavydovW. S. Snyder
C. SpinosaPermian Research Institute
Department of Geosciences,Boise State UniversityBoise, ID 83725, USA
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Permian Stratigraphic Units of the WesternVerkhoyansk Mountains and Their Correlation
Aleksandr G. Klets, Igor V. Budnikov, Ruslan V.Kutygin, Vitaly S. Grinenko
The Permian of the western Verkhoyansk Mountains is character-ized predominantly by marine strata exposed in continuous sec-tions with dominantly boreal type faunas. The Verkhoyansk re-gion is geographically intermediate and as such, has importantsignificance for interregional correlation (Budnikov and others,1997). The history of the formation of Permian deposits of theVerkhoyansk region is characterized by certain packages of strata,each of which is initially predominantly marine, and which laterbecomes less marine and more nearshore. These sedimentologiccycles can be directly correlated with transgressive-regressivecycles associated with eustatic fluctuations of worldwide oceanlevel. Each cycle is characterized by a regular distribution offaunal complexes (Permophiles, 28, 30). In Permian strata of thewestern Verkhoyansk Mountains six sedimentologic cycles areassociated with faunal and floral developmental stages. These arethe Khorokitsky, Echiisky, Tumarinsky, Delenzhinsky,Dulgalakhsky and Khalpirsky stratohorizons. These strata con-tain faunal complexes with affinities to the Uralian and toNorth-American provinces. Regional complexes of the westernVerkhoyansk Mountains are correlated with stratigraphic units ofUral region and with the Permian chronostratigraphic scale ac-cepted by Guadalupian Symposium (Guadalupe II) (Table 1). Thestudy was supported by The Russian Fund for Fundamental In-vestigations, grant N 97-05-65209 and 97-05-64847.
ReferencesI.V.Budnikov, A. G. Klets, V.S.Grinenco, R.V.Kutygin. 1996.
Permian of East Yakutiya. Permophiles No. 28, p. 27-29.I.V.Budnikov, A. G. Klets, V. S. Grinenco, R. V. Kutigin. 1997.
Permian of Barai River (West Verchoyanie). PermophilesNo. 30, p.26-27.
I.V.Budnikov, A. G. Klets, V. S. Grinenco. 1997. WestVerkhoyanye is the key region to solve the main strati-graphic problems of Upper Paleozoic of Siberia. Proceed-ings of The XIII International Congress on The Carbonifer-ous and Permian. Krakow, Poland. Part 1. Warszawa. p.105-108.
Aleksandr G. KletsInstitute of Geology of Oil and Gas, Siberian Branch of
Russian Academy of SciencesNovosibirsk, Russia
Igor V. BudnikovSiberian Research Institute of Geology
Geophysics and Mineral ResourcesNovosibirsk, Russia
Ruslan V.KutyginInstitute of Geology
Yakutsk, Russia
Hindeodus parvus: Advantages and Problems
Wang Cheng-yuan
Conodonts as a leading fossil group for Permian and Triassicbiostratigraphy are commonly accepted by nearly allpalaeontologists and geologists. Hindeodus parvus, as an indexspecies for defining the base of the Triassic, is also commonlyaccepted by the majority of the members of the International Work-ing Group on the Permian-Triassic Boundary (PTBWG) since1988. The Permian-Triassic boundary beds and their conodontshave been intensively studied in the recent years. Much progressand achievements have been obtained in the study of conodonts.Hindeodus parvus possesses the many advantages for definingthe base of the Triassic: wide distribution, occurring in low andhigh latitudes and in shallow and deep-water facies, it is easy toidentify, and therefore it is much better than gondolellid conodonts.But there are still many discrepancies in the conodont study, espe-cially the problems concerning Hindeodus parvus: the definition(the definition of Hindeodus parvus and the biostratigraphic defi-nition for the base of the Triassic), taxonomy (at the genus, spe-cies, subspecies and morphotype levels), evolutionary lineage,zonation, the position of the P/T boundary and the contact rela-tionship of the P/T boundary beds at the Meishan sections whichare ranked as the first candidate section for the GSSP of the baseof the Triassic. We must face the realities and admit the discrep-ancies, instead of avoiding the problems. It is not workable toselect a GSSP for the base of Triassic before these problems havebeen solved.
The purpose of this paper is not to evaluate the different view-points around Hindeodus parvus, but to arouse the members ofPTBWG to notice the existing problems, and try to pave a way tosolve the problems.
The Advantages of using H. parvus as the marker for the P/T Boundary
Hindeodus parvus as a biostratigraphic marker for the base ofthe Triassic is generally accepted by the majority members of thePTBWG. It is really an excellent species for defining the base ofthe Triassic. Its advantages are obvious:
1. Hindeodus parvus has a world-wide distribution. It has beenfound at least in 20 localities in China, and also in Kashmir, SaltRange, Transcaucasia, Iran, Italy, Austria, Hungary, United States,Greenland and British Columbia. It occurs in low and high lati-tudes. Some people (Baud, 1996, and others) consider that the H.parvus occurs only in shallow water faces, and because nearly allconodont zonal species were selected from the deep water facies,they concluded that the H. parvus was not suitable to be an indexfossil for defining the base of the Triassic. But H. parvus is alsopresent in deep water facies (Gullo & Kozur, 1993). It has a
Vitaly S.GrinenkoState Yakutsk Exploration-Survey Expedition
Yakutsk, Russia
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world-wide distribution both in ammonoid-bearing pelagic facies(rare) and in ammonoid-free shallow water facies (common). Asa free-swimming animal, the conodonts lived in different depthzones. Hindeodus lived in shallow euphotic zone, the Hindeodusbiofacies was mostly deposited in shallow water facies and rarelyin deep water facies. Clarkina lived in deep euphotic zone andbelow the storm wave base. The Clarkina biofacies was mostlydeposited in basinal and slope facies, and partly in outershelf fa-cies. Moreover, H. parvus exists not only in the Tethys realm butalso in the Boreal realm and in the Perigondwana area. It is veryimportant for the correlation of the Boreal faunas with the Tethyanstandard. On the contrary, the gondolellid species such as Clarkinameishanensis that was suggested as an index fossil for the base ofthe Triassic (Orchard et al.,1994 and Orchard & Tozer, 1997) isnot present in the Perigondwana and Arctic regions. So far, no-where in the world has been found a section from which only thepelagic gondolellid conodonts are present. We have to recognisethat true pelagic facies that accumulated during the time intervalcovering the Permian-Triassic boundary is very rare and very lim-ited. Not any Clarkina species as Wardlaw & Mei (1998) sug-gested could be found both in the Boreal and Tethyan realms andcould be index fossil for the base of the Triassic
2. Only the Hindeodus lineage can be traced bed by bed fromthe Permian-Triassic boundary beds, the Hindeodus evolutionarylineage at the Meishan sections has revealed a high-resolutionconodont zonation. This conodont lineage can be recognised inmany sections in the world; even so there are still problems to besolved. On the contrary, so far nowhere in the world has a succes-sion from Pseudotirolites (or Paratirolites ) Zone-to-OtocerasZone been established in the same section.
3. The first appearance of H. parvus is a unique biostratigraphichorizon and it is the level that is close to the event stratigraphicboundary. This biostratigraphical boundary lies, in the Meishansection,15 cm above the event boundary, and about 5 cm abovethe dC13 minimum. It nearly coincides with the beginning of thedistinct anoxic event that can be observed in most basinal faciesin the world (Wignall & Hallam, 1991).
4. The H. parvus boundary has several biostratigraphic criteriaand other criteria which can be used as auxiliary markers for thebase of the Triassic:
A. Biostratigraphic auxiliary markers:a. The extinction of Clarkina deflecta, C.dicerocarinata,
C.changxingensis, C.meishanensis, Hindeodus latidentatus, H.changxingensis and H. typicalis.
b. The first appearance of Isarcicella staeschei, I.isarcica,Claraia wangi and Ophiceras commune.
B. Other auxiliary criteria:a.. Lithostratigraphic event boundary, the base of the boundary
clay at the Meishan section (Boundary bed 1, or bed 25).b. The boundary of the minimum in dC13 value at the P/T bound-
ary beds.c. Anoxic event, the base of the upper part of the boundary clay
bed 1 or the bed 26 at the Meishan section;These auxiliary criteria are very helpful and useful for the recog-nition of the base of the Triassic.
Problems of the H. parvus BoundaryAs mentioned above, there are still many discrepancies in the
conodont study, especially the taxonomical problems and the un-derstanding of Hindeodus parvus. Following problems are noted:
The definition for the base of Triassic:Six different conodont-based definitions for the base of the Tri-
assic have been proposed by conodont workers in the recent years:1. The First Appearance Datum (FAD) of Hindeodus parvus. It
was first proposed by Yin et al. in 1988;2. The FAD of Hindeodus parvus Morphotype 1. It was first
proposed by Wang in 1994 based on the study of the conodontsfrom the Meishan sections;
3. The FAD of Hindeodus parvus erectus. It was first proposedby Kozur in 1996. He named the Hindeodus parvus Morphotype1 as a new subspecies: H. parvus erectus.
4. The FAD of Clarkina meishanensis. It was first proposed byMei in 1996 (MS).
5. The FAD of Hindeodus parvus proparvus. Zhu et al.(1997)named six new subspecies of Hindeodus parvus based on the eightconodont specimens illustrated in the previous publications. Theyproposed the so-called typical Hindeodus parvus, that is hisHindeodus parvus proparvus, for defining the base of Triassic.Zhu et al. (1997) also use Hindeodus parvus Morphotype 2 andtheir own new subspecies H. parvus lepingensis, H. parvusyangouensis, H. parvus meishaensis, H. parvus baoqingensis andHindeodus dingi as well as their four morphotypes (morphotype3 to morphotype 6) of Hindeodus parvus to define the base ofTriassic;
6. The FAD of one species of a gondolellid element (or Clarkinaspecies). It was proposed by Orchard et al. (1996) and Wardlaw& Mei (1998, p.4), but they did not select a discrete gondolellid(Clarkina) species as an index fossil.
Which definition is the best for the base of Triassic ? There isno agreement among the conodont workers. They have to discussand to get an agreement for the definition for the base of the Trias-sic. To select a reliable biostratigraphic definition is very impor-tant for the defining the GSSP for the base of the Triassic. Thenon-conodont specialists of PTBWG should know the importancesolving the existing discrepancies. The present author is in favourof using the Hindeodus parvus Morphotype 1 or H. parvus erectusto define biostratigraphically the base of the Triassic.
Taxonomy (discrepancies on generic level):1. Most conodont workers have assigned the conodont species
parvus to the conodont genus Hindeodus Rexroad et Furnish, 1964(Kozur et al., 1995, 1996,1997; Wang, 1994, 1995; Wang et al.,1996,1997);
2. Ding et al. (1995) insisted that the species parvus should beassigned to conodont genus Icarcicella Kozur, 1975
Taxonomy (species, subspecies and morphotype):Following morphotypes and subspecies of Hindeodus parvus
have been proposed:1. Hindeodus parvus (Kozur & Pjatakova, 1976). It should be
pointed out that Kozur & Pjatakova have selected two holotypesfor Hindeodus parvus. In 1976 they appointed one holotype(1976,fig.1b) and in 1977 they selected another holotype for same spe-cies(1977, pl.1, fig.17, as same as their 1976 fig.1a). Obviouslythe first holotype(1976,fig.1b) is valid. The two selected holo-types both come from the Ophiceras commune Zone, andHindeodus parvus sensu Kozur & Pjatakova (1976,1977) is dif-ferent from Hindeodus parvus recorded from the Otoceras Zoneand described by Matsuda (1981);
2. In 1990 Kozur formally named two morphotypes for his two
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holotypes Hindeodus parvus, Morphotype 1 is his second holo-type, Morphotype 2 is his first holotype respectively. He consid-ered that the Morphotype 1 was more typical and had stable char-acters.
3. In 1996, Kozur named two subspecies for Hindeodus parvus.Hindeodus parvus Morphotype 1 was renamed Hindeodus parvuserectus, Hindeodus parvus Morphotype 2 was renamed Hindeodusparvus parvus. In the meantime he accepted Hindeodus parvusanterodentatus (Dai et al., 1989).
4. Zhu et al. (1996) named four morphotypes for Hindeodusparvus based on the illustrated specimens in the literature. Thespecimen of Matsuda (1981, pl.5,fig.2) was named by them as H.parvus Morphotype 3, the specimen of Matsuda (1981, pl.5, fig.1)was named H. parvus Morphotype 4 at the same time. The Chi-nese specimens that are illustrated in Zhu et al (1994) and depos-ited in Nanjing Institute of Geology and Palaeontology, AcademiaSinica, were named another two morphotypes. The specimen ofZhu et al. (1994, pl.1, fig.1) was named H. parvus Morphotype 5,while the specimen (Zhu et al., 1994, pl.1, fig.6) was named H.parvus Morphotype 6.
5. Zhu et al. (1997) named six new subspecies for Hindeodusparvus based on eight specimens illustrated in previous papers,i.e. Hindeodus parvus baoqingensis (The specimen of Ding etal., l995, pl. 1,fig. 1a), H. p. meishanensis (the specimen of Wang,C. Y., 1995, pl. III, fig. 6), H. p. proparvus (the specimen of Zhuet al., 1994, pl.1, fig.1, and 6), H. p. lepingensis (the specimen ofZhu et al., 1994, pl. 1, fig. 3 and the specimen of Ding et al., 1995,pl. 1 fig. 4), H. p. dingi (the specimen of Ding et al., 1995, pl. I,fig. 5), H. p. yangouensis (the specimen of Zhu et al., 1994, pl. I,fig. 2), they also keep the two morphotypes of Hindeodus parvusnamed by Kozur (1989) and their other four morphotypes namedin 1996. They “appointed” that the three specimens described byMatsuda (1981, pl. 5, figs. 1-3) should be Hindeodus parvusparvus. Their H. parvus parvus is different from the H. parvusparvus named by Kozur (1996). It has to be pointed out that Zhuet al. (1997) did not have their own conodont specimens on whichthey created new subspecies and morphotypes. In addition, theynever selected the holotypes for their new taxa, they also nevergave a formal description for their new subspecies. They onlymentioned in their papers that they “propose” some specimen asnew subspecies and give a new name. Based on above hardlyanybody can accept these six proposed subspecies and four newmorphotypes. It is impossible that the Hindeodus parvus has somany morphotypes and so many subspecies as named by Zhu etal. (1996,1997). Zhu et al’s papers are characterised byoversplitting of subspecies or morphotypes; it makes no sense;the numerous so-called morphotypes or subspecies arestratigraphically not relevant, only represent variation within onespecies or subspecies.
Anyway, the taxonomical situation of Hindeodus parvus is veryconfusing, especially at the subspecies or morphotype level. TheHindeodus parvus really has a few morphotypes or subspecies.These morphotypes or subspecies have different ranges and theirFADs are also different. If we use Hindeodus parvus to definethe base of the Triassic, we can not precisely fix the position ofGSSP, because the Hindeodus parvus has different subspecies ormorphotypes with different ranges and FADs. It is reasonable toselect one morphotype or one subspecies to define the base of theTriassic. Conodont workers should discuss the problems and getan agreement on the taxonomy of Hindeodus parvus. The present
author still considers that the best selection is to use the Hindeodusparvus Morphotype 1 or Hindeodus parvus erectus or evenHindeodus erectus as the definition for the base of Triassic.
Evolutionary lineage:Following four different evolutionary lineages of Hindeodus
parvus have been proposed in the recent years:1. Zhang et al. (1995, in Yin, 1996), Ding et al. (1996) pro-
posed a evolutionary lineage for Hindeodus parvus, i.e., Hindeoduslatidentatus ®Isarcicella parva ®I. turgidus ®I. isarcica;
2. Wang (1996) proposed a evolutionary lineage for theHindeodus parvus, i.e. Hindeodus latidentatus ®H. parvus®Isarcicella staechei ®I. isarcica;
3. Kozur (1996) proposed an evolutionary lineage for theHindeodus parvus, i.e. Hindeodus latidentatus preparvus ®H.parvus erectus ®Isarcicella isarcica;
4. Zhu et al. (1996) proposed their own evolutionary lineage forthe different morphotypes of the Hindeodus parvus, that is,Hindeodus parvus Morphotype 5®H. parvus Morphotype 2 ®H.parvus Morphotype 3 ®H. parvus Morphotype 4 ®H. parvusMorphotype 1 ®H. parvus Morphotype 6. This is an inferredevolutionary lineage (Zhu et al., 1996,p. 3).
It is a common rule that a species or subspecies, if its forerun-ner and descendent is not clear, should not be selected as the indexfossil for defining the base of a Period or a Stage. Conodont work-ers have to have a common agreement on the evolutionary lineageof the Hindeodus parvus. The present author is in favour of theHindeodus latidentatus prepavus ®H. parvus erectus—I. staechei® I. isarcica lineage.
Conodont zonation for the Earliest Triassic:Four different successions of conodont zones for the earliest
Triassic have been proposed:1. Zhang et al. (1995) proposed the following conodont zones
for the earliest Triassic, in ascending order: Isarcicella parva Zone ®I. isarcica Zone ®Clarkina carinata-C. planata Zone;
2. Ding (1996, p. 69) cited the parvus Zone and isarcica Zoneas the earliest Triassic of the Meishan section.
3. Kozur (1995, 1996) proposed the conodont zones for theearliest Triassic as follows:Shallow water facies:Hindeodus parvus Zone ®I. isarcica Zone;Pelagic facies:Clarkina carinata-C. planata Zone (Kozur, 1995, 1996).
4. Wang (1996, 1997) proposed the earliest Triassic conodontzones:Shallow water facies (Hindeodus biofacies):Hindeodus parvus Zone ®Isarcicella staeschei Zone ®I. isarcicaZone ®H. postparvus Zone.Deep water facies (Clarkina biofacies):Clarkina carinata Zone ®C. planata Zone.
There is no agreement among the conodont workers about theconodont zones for the earliest Triassic. The present author stillconsiders that the fourth scheme (Wang, 1996, 1997) is accept-able.
The position of the P/T boundary:At least 13 different definitions of the P/T biostratographic
boundary have been presented by various different authors as
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summarised by Wang (1994b, p. 236-237). The concrete posi-tions of the base of Triassic at the Meishan sections have at leastfour different schemes (Wang, 1994b, p. 241):
1. the base of bed 25 (boundary clay bed, Sheng at al., 1984;Yin, 1988, 1994; Mei, 1996; Zhu et al., 1997);
2. the base of bed 26 (Zhang, 1984; Sheng et al., 1987);3. the base of bed 27 (Clark et al., 1986);4. within the boundary bed 2 (= bed 27, or at the base of AEL882-
3, Wang, 1994, 1995, 1996, 1998,Wang et al., 1997, Metcalfe etal., 1997; or at the base of bed 27c, Yin et al., 1995, 1996).
At present most of the members of PTBWG have accepted thefourth scheme, but Mei (1996) and Zhu et al. (1997) still insist touse the first scheme. The present author placed the P/T biostrati-graphic boundary with considerable confidence within the bound-ary bed 2 (the fourth scheme).
Contact relationships at the P/T boundary beds:Chinese specialists have quite different opinions about the con-
tact relationships of the P/T boundary beds at the Meishan sec-tions:
1. Most peoples consider that the P/T boundary beds at theMeishan sections are continuous marine deposits (Wang, 1994,1995, 1998; Wang et al. 1996; Kozur et al., 1996; Yin et al, 1996).Wang (1994) especially emphasised that the boundary beds at theMeishan sections are continuous marine deposits that accumu-lated below storm wave base;
2. Jin et al. (1994) and Sheng et al. (1994) stressed with thesame sentence in their two papers that: “The so-called boundaryclay at the top of the Changhsingian is in fact a residual bed on thenon-depositional surface”, which means, the P/T boundary bedsat the Meishan sections do not represent continuous sedimenta-tion. Zhu et al. (1997) even proposed that there is a sedimentarygap at the top of the Changhsing Limestone, they called it an “emptyarea”.
If there is a sedimentary gap between the P/T Systems, theMeishan sections can not be selected as stratotype for the GSSPof the base of the Triassic. This is a very important problem onwhich we have to have a common agreement. The present authorstill insists that the P/T boundary beds at the Meishan sections areindeed continuous marine deposits that accumulated below stormwave base. There are no sedimentary gap in the boundary beds.
So many discrepancies about the Hindeodus parvus are present:its definition, taxonomy, evolutionary lineage, and zonation as wellas the level of the base of the Triassic and the contact relation-ships of P/T boundary beds at the Meishan sections, all of these,we have not gain international agreement. The conodonts are ab-solutely important for the P/T boundary beds and the GSSP of thebase of the Triassic. The conodont workers must discuss and clarifyall the crucial problems about Hindeodus parvus, especially thefollowing problems are crucial:
1.The conodont definition of the base of Triassic: Hindeodusparvus or H. parvus erectus (or H. parvus Morphotype 1)? Thedifferent subspecies of Hindeodus parvus have different FADs ornot?
2. The forerunner and descendent of the Hindeodus parvus orH. parvus erectus.
3. The conodont zonation for the earliest Triassic.4. The contact relationships of the P/T boundary beds at the
Meishan sections.The present author has orally proposed to the Chairman of
PTBWG, Prof. Yin, H. F., to have a meeting to discuss these prob-lems. The present author here again calls to convene an interna-tional meeting in China, all of the conodont workers who havestudied the conodonts of the P/T boundary beds should be invitedto attend this meeting. Prof. Yin, H. F as a Chairman of PTBWGshould preside over this meeting. We must be clearly aware thatwe can not finally vote to the GSSP of the base of Triassic beforewe gain an international common agreement about the Hindeodusparvus.
AcknowledgementsThe author thanks very much the Nanjing Institute of Geology
and Palaeontology, Academia Sinica for financial support fromthe special funds for this study.
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Zhang Ke-xin, Ding Mei-hua, Lai Xu-long & Liu Jin- hua,1996: Conodont sequences of the Permian- Triassic bound-ary strata at Meishan section, South China. In Yin Hong-fu( ed.):NSFC project: The Palaeozoic- Mesozoic boundarycandidates of Global stratotype section and point of thePermian- Triassic bounadry. 57-64. China University ofGeosciences Press.
Zhu Xiang-shui, Lin Lian-sheng & Lu Hua, 1996: Recommenda reference section of GSSP. Journal of Jiangxi NormalUniversity, 20(3):264-268.
Zhu Xiang-shui & Lin Lian-sheng,1997: Typical Hindeodusparvus and its significance and discussion on P/T boundary.Journal of Jiangxi Normal University, 21(1):88-95.
Zhu Xiang-shui, Lin Lian-sheng & Zhong Ye-xi, 1997: Thefurther of Hindeodus parvus in P/T bounadry bed inNorthern Jiangxi, and rediscussion of P/T boundary. Journalof Jiangxi Normal University, 21(2):1-5.
Zhu Xiang-shui, Zhong Ye-xi & Lu Hua, 1997: The correlationof the P/T boundaries sections between Dongling, Yangouand Meishan regions in the eastern Tethys. Journal ofJiangxi Normal University, 21(1):1-5.
Zhu Xiang-shui, Lin Lian-sheg & Hu Zhong, 1997: Thediscovery of the Longtanian conodonts from Qibaoshan,Shanggao County, Jiangxi, and discussion onGallowayinella Time. Journal of Jiangxi Normal University,21(2):174-177.
Wang Cheng-yuanNanjing Institute of Geology and Palaeontology
Academia SinicaNanjing, 210008
ChinaReviewer Comment:
Wardlaw and Mei (1998) did not select a discrete gondolellid(Clarkina) species as an index fossil because they were not pro-posing an alternative definition of the Permian-Triassic bound-ary. They fully agree with using the first appearance datum ofHindeodus parvus as the boundary definition. They were point-ing out that Clarkina species are useful throughout the Lopingianand C. meishanensis characterises the boundary interval at theMeishan section and implied it would be a good accessory iden-tifier not the boundary definer.
(B. R. Wardlaw)
14
Permian Brachiopods from the Selong XishanSection, Southern Xizang (Tibet): PreliminaryAssemblages and Stratigraphical Implications
Shuzhong Shen, N.W. Archbold, G.R. Shi andZ.Q. Chen
Different opinions about the taxonomy and biostratigraphy ofconodonts and brachiopods from the boundary beds at the SelongXishan section have been previously presented by Zhang (1974),Yin and Guo (1975), Rao and Zhang (1985), Wang et al. (1989),Xia and Zhang (1992), Wang et al. (1993), Shen and Jin (1994)and Orchard et al. (1994). Recently, some detailedlithostratigraphical, biostratigraphical and geochemical studies onthe collections and new results on the Permian-Triassic boundaryhave been studied and subsequently reported by Jin et al. (1996),Mei (1996), Wang et al., (1997), and Shi and Shen (1997). How-ever, neither detailed biostratigraphy nor systematic study of bra-chiopods, despite its unique abundance in this section, has beencarried out for the sequence of the Selong Group. Moreover, thedebate about the correlation of the Selong Group between Xizangand other regions has continued for tens of years.
More than 600 specimens, some 42 brachiopod species belong-ing to 30 identifiable genera and 2 unidentifiable genera from theSelong Group of the Selong Xishan section are collected and iden-tified. Brachiopods from the Selong Group suggest an age possi-bly ranging from late Capitanian (Midian) to Changhsingian interms of the framework of the newly proposed three-fold Permiantimescale (Jin et al., 1997). Brachiopods in the uppermost SelongGroup demonstrate a clear relationship with those found lower inthe Group. They are characteristically dominated by Gondwananand bipolar elements. Spiriferella rajah (Salter) and S. nepalensisLagrand-Blain exist through the whole Selong Group.Taeniothaerus densipustulatus sp. nov., Marginalosia kalikotei(Waterhouse), Trigonotreta lightjacki Archbold and Thomas,Neospirifer (Neospirifer) kubeiensis Ting range up to about 1 metrebelow the Otoceras Bed. The brachiopods in the Selong Groupmay be roughly divided into two stages. In the lower and middleparts of the Selong Group in the Selong Xishan section brachio-pods are relatively low in diversity but high in abundance andpredominated by large spiriferids with thick shells such asNeospirifer (Neospirifer) kubeiensis Ting, Spiriferella rajah(Salter) and an aulostegoid Taeniothaerus densipustulatus sp. nov.;but in the upper part (about 5 m thick) of the Selong Group bra-chiopods are more diversified and predominated by elements at-tached by the pedicle with relatively small size although most spe-cies in the lower stage are still present. Three brachiopod assem-blages are recognised. The Marginalosia-Composita Assemblagein the lower part of the Selong Group is considered to be of lateCapitanian (Midian) to early Wuchiapingian (Djhulfian) age. Theoverlying Chonetella nasuta Zone (Zhang and Jin, 1976; Jin, 1985)is well recognizable in the Selong Xishan section, which could befurther divided into Costatumulus tazawai-Retimarginiferaxizangensis Assemblage and Stenoscisma gigantea-Nakimusiellaselongensis Assemblage in ascending order, and brachiopods inthis zone closely resemble those from the Senja Formation in theDolpo district of Nepal, the Kalabagh Member and the ChhidruFormation in the Salt Range, Pakistan and the middle part of the
Zewan Formation in Kashmir, and be considered to be largelyWuchiapingian (Djhulfian). The age of the Coral Bed of Jin et al.(1996) cannot be determined from brachiopods. But aChanghsingian age assignment of the Martinia-“Waagenites” Bed(=Waagenites Bed of Jin et al., 1996) is preferred (Table 1). Itappears that there is no major hiatus present in the whole SelongGroup in terms of brachiopod assemblages. A statistical analysisat the generic level shows that the Selong fauna has a strong affin-ity with those from Nepal and Western Australia, as well as Timor,Kashmir, the Salt Range and the Karakorum Range of Pakistan,and no substantial relationship with South China, Transcaucasiaand the eastern Qiangtang terrane.
AcknowledgementsThis paper is supported by the Australian Research Council (GrantNo. A0503617156).
ReferencesArchbold, N.W., 1987. South Western Pacific Permian and
Triassic Marine Faunas: Their Distribution and Implicationsfor Terrane Identification. In Terrane Accretion and Oro-genic Belts. Leitch, E.C., and Scheibner, E. (eds.),Geodynamic Series 19:119-127.
Archbold, N.W., 1993. A zonation of the Permian Brachiopodfaunas of western Australia. In Gondwana Eight-Assembly,Evolution and Dispersal. Findlay, R.H., Unrug, R., Banks,M.R., and Veevers, J.J. (eds.), 313-321. Rotterdam: A.A.Balkema.
Archbold, N.W., and Bird, P.R., 1989. Permian Brachiopodafrom near Kasliu Village, West Timor. Alcheringa 13(1-2):103-123.
Broili, F., 1916. Die Permischen Brachiopoden von Timor. InPalaeontologie von Timor. Wanner J. (ed.), 7:1-104.Stuttgart.
Diener, C., 1897. Himalayan Fossils. The PermocarboniferousFauna of Chitichun No.1. Geological Survey of India,Memoirs, Palaeontologia Indica, Ser. 15, 1(3):1-105.
Diener, C., 1903. Permian Fossils of the Central Himalayas.Geological Survey of India, Memoirs, PalaeontologiaIndica, Ser. 15, 1(5):1-204.
Furnish, W.M., 1973. Permian Stage Names. In StratigraphicBoundary Problems: Permian and Triassic of West Paki-stan. Kummel, B., and Teichert, C. (ed.), 522-548. KansasUniversity Press.
Grant, R.E., 1970, Brachiopods from Permian-Triassic Bound-ary Beds and Age of Chhidru Formation, West Pakistan. InStratigraphic Boundary Problems: Permian and Triassic ofWest Pakistan. Kummel, B., and Teichert, C. (eds.), Univer-sity of Kansas, Department of Geology, Special Publication4:117-151.
Hamlet, B., 1928. Permische Brachiopoden, Lamellibranchiatenund Gastropoden von Timor. Jaarboek van het Mijnwezen inNederlandsch Oost-Indie, Gravenhage 56(2):1-115.
Jin Yugan, 1985. Permian Brachiopoda and Paleogeography ofthe Qinghai-Xizang Plateau. Palaeontologica Cathayana2:19-71.
Jin Yugan, Liang Xiluo, and Wen Shixuan, 1977. Additionalmaterial of animal fossils from the Permian deposits on thenorthern slope of mount Qimolangma Feng. ScientiaGeologica Sinica 3:236-249.
15Table 1. Brachiopod assemblages in theSelong Xishan section and their correlation with other faunas in the Peri-Gondwanan region.
16
Jin Yugan, Shen Shuzhong, Zhu Zhili, Mei Shilong and WangWei, 1996. The Selong Xishan section, candidate of theglobal stratotype section and point of the Permian-Triassicboundary. In The Palaeozoic- Mesozoic Boundary Candi-dates of the Global Stratotype Section and Point of thePermian-Triassic Boundary, Yin Hongfu (ed.), 127-137.China University of Geosciences Press, Wuhan, China.
Jin Yugan, Wardlaw, B.R., Glenister, B.F., and Kotlyar, G.V.,1997. Permian chronostratigraphic subdivisions. Episodes20(1):10-15.
Mei Shilong, 1996. Restudy of conodonts from the Permian-Triassic boundary beds at Selong and Meishan and thenatural Permian-Triassic boundary. In Centennial MemorialVolume of Prof. Sun Yunzhu: Palaeontology and Stratigra-phy, Wang, Hongzhen, and Wang Xunlian (eds.), 141-148,China University of Geoscience Press
Nakazawa, K., Kapoor, H.M., Ishii, K., Bando, Y., Okimura, Y.,and Tokuoka, T., 1975. The Upper Permian and the LowerTriassic in Kashmir, India. Kyoto University, Faculty ofScience (Geology and Mineralogy), Memoirs 42(1):1-106.
Orchard, M.J., Nassichuk, W.W., and Rui Lin, 1994. Conodontsfrom the lower Griesbachian Otoceras latilobatum Bed ofSelong, Xizang and the position of the Permian-Triassicboundary. Canadian Society of Petroleum Geologists,Memoir 17:823-843.
Rao Rongbiao, and Zhang Zhenggui, 1985. A discovery ofPermo-Triassic transitional fauna in the Qomolangma Fengarea: its implications for the Permo-Triassic boundary.Xizang Geology 1:19-31.
Reed, F.R.C., 1944. Brachiopoda and Mollusca from theProductus Limestones of the Salt Range. Geological Surveyof India, Memoirs, Palaeontologia Indica 23(2):1-678.
Shen Shuzhong, and Jin Yugan, 1994. Brachiopods fromPermian-Triassic boundary beds of the Selong Xishansection. Abstracts of International Symposium on Permianstratigraphy, Environments and Resources, Guiyang,China, 27-28.
Sheng Jinzhang, and Wang Yujing, 1981. Permian fusulinidsfrom Xizang with reference to their geographical provincial-ism. Acta Palaeontologica Sinica 20(6):546-551.
Shi, G.R., and Shen Shuzhong, 1997. A Late Permian brachio-pod fauna from Selong, Southern Xizang (Tibet), China.Proceedings of the Royal Society of Victoria 109(1):37-56.
Waagen, W., 1883-1885. Salt Range Fossils. I. Productus-Limestone Fossils. Geological Survey of India, Memoirs,Palaeontologia Indica, Ser. 13, 4(2-5):391- 770.
Wang Wei, Shen Shuzhong and Zhu Zhili, 1997. Carbon isotopecharacters of the Permian Triassic boundary section atSelong, Xizang (Tibet), China and their significance.Chinese Science Bulletin 4:406-408.
Wang Yugang, Chen Chuzhen, Rui Lin, Wang, Zhihao, LiaoZhuo-Ting, and He Jinwen, 1989. A potential globalstratotype of Permian-Triassic boundary. Chinese Academyof Sciences, Developments in Geoscience. Contribution to28th International Geological Congress, 1989, Washington,D.C. USA. 221-229. Science Press, Beijing.
Wang Zhihao, Chen Chuzhen, and Liao Zhuoting, 1993. Somequeries about the paper “Age of the Selong Formation inXishan, Selong of Xizang (Tibet) and the Permian-Triassicboundary”. Journal of Stratigraphy 17(3), 223, 237-239.
Wardlaw, B.R., and Pogue, K.R., 1995. The Permian of Paki-stan. In The Permian of Northern Pangea 2, SedimentaryBasins and Economic Resources, 215-224, Springer-Verlag,Berlin.
Waterhouse, J.B., 1978. Permian Brachiopoda and Molluscafrom North-West Nepal. Palaeontographica, Abt. A, 160(1-6):1-175.
Waterhouse, J.B., and Gupta, V.J., 1983. A Faunule from theLamnimargus himalayensis Zone in the Upper Shyok Valley,Southern Karakorum Range. In Stratigraphy and Structureof Kashmir and Ladakh Himalaya. Contributions toHimalayan Geology, Gupta V.J., (ed.) 2:234-245.
Waterhouse, J.B., and Shi, Guang R., 1990. Late PermianBrachiopod Faunules from the Marsyangdi Formation,North Central Nepal, and the Implications for the Permian-Triassic Boundary. In Brachiopods Through Time,MacKinnon, D.I., Lee, D.E., and Campbell, J.D. (eds.), 381-387. Rotterdam: A.A. Balkema.
Xia Fengsheng, and Zhang Binggao, 1992. Age of the SelongFormation in Xishan, Selong of Xizang (Tibet) and thePermian-Triassic boundary. Journal of Stratigraphy16(4):256-363.
Yin Jixiang, and Guo Shizeng, 1975. Stratigraphy of the MtJolmolangma and its northern slope, with a discussion aboutcorrelation of Sinian-Cambrian and Carboniferous-Permianwith adjacent areas. In A report of the Scientific expeditionin the Mt. Jolmolangma region (1975) (Geology), 1-71,Science Press, Beijing.
Zhang Binggao, 1974. The Permian System. In A report ofScientific expedition in the Mt. Jolmolangma Region(Geology), 66-68, Science Press, Beijing, China.
Zhang Shouxin, and Jin Yugan, 1976. Late Paleozoic Brachio-pods from the Mount Jolmo Lungma Region. In A Report ofScientific Expedition in the Mount Jolmo Lungma Region(1966-1968) 2, 159-271, Science Press, Beijing.
Shuzhong ShenN. W. Archbold
G. R. Shi Z. Q. Chen
School of Ecology and Environment,Deakin University, Rusden Campus,
662 Blackburn Road, Clayton,Victoria 3168, Australia
[email protected]@deakin.edu.au
[email protected]@deakin.edu.au
17
Permian Tetrapod Biochronology
Spencer G. Lucas
IntroductionPermian tetrapod (amphibian and reptile) fossils are broadly
distributed across Pangea (fig. 1) and have long provided a basisfor nonmarine biostratigraphy and biochronology. Here, I assessthe current status of Permian tetrapod biostratigraphy andbiochronology.
Previously proposed subdivisionsRelatively few attempts have been made to delineate a global
tetrapod biostratigraphy or biochronology of the Permian (fig. 2).Romer (1966, 1973) divided the Permian tetrapod record into three“stages” that essentially correspond to a threefold subdivision ofthe Permian into Early (Asselian-Artinskian), Middle (Kungurian-Kazanian) and Late (Tatarian) (fig. 2). As Romer noted, cotylo-saurs and pelycosaurs dominate the early stage, best known fromNorth America and the western European Rotliegende. The inter-mediate stage is dominated by primitive synapsids and knownmostly from South Africa and the Russian Urals. The third stage(Romer also called it the “final phase”) is dominated by advancedtherapsids known mostly from South Africa.
Anderson and Cruickshank (1978) recognized the same globaldivisions as Romer, but they recast them as “empires” (essentiallythe same concept as “chronofaunas” of Olson, 1952). Andersonand Cruickshank (1978, charts 2.1-2.2) also listed 17 Permiantetrapod zones, but did not explicitly define them (fig. 2). How-ever, from their chart 2.1 it is clear that zones 1 through 12 arebased on Texas stratigraphic units (1 = Pueblo Formation; 2 =Moran Formation; 3 = Putnam Formation; 4 = Admiral Forma-tion; 5 = Belle Plains Formation; 6 = Clyde Formation; 7 = LeudersFormation; 8 = Arroyo Formation; 9 = Vale Formation; 10 = ChozaFormation; 11 = San Angelo Formation; and 12 = Flowerpot For-mation), zones 13 and 14 are equivalent to Russian zones pro-posed by Efremov (13 = Zone I; 14 = Zones II and III) and theyoungest zones are those of the South African Karoo basin (15 =Tapinocephalus Zone; 16 = Cistecephalus Zone; 17 =Daptocephalus [= Dicynodon] Zone).
Cooper (1982) published a Middle to Late Permian tetrapodbiostratigraphy very similar to Zones 11-17 of Anderson andCruickshank (1978), but with different terminology (fig. 2). Thus,Cooper’s (1982) Dimacrodon Zone is based on the vertebrate fossilassemblages of the San Angelo and Flowerpot Formations of Texas(Olson, 1962); his Otsheria Zone = Russian Zone I; his VenyukoviaZone = Russian Zone II; and his Robertia Zone = theTapinocephalus Zone. Cooper (1982) assigned the LystrosaurusZone to the Permian, though most workers consider it to be Trias-sic.
There have been no other explicit attempts to develop a globalbiostratigraphy or biochronology of Permian tetrapods, thoughcorrelation charts of the Permian tetrapod record are numerous(e.g., Romer, 1966; Olson, 1989; Olson and Chudinov, 1992).Nevertheless, two regional schemes of Permian tetrapod biostratig-raphy have been extremely important (fig. 2). Efremov (e.g., 1937,1940) proposed a succession of four tetrapod “zones” for the Per-mian of the Russian Urals. Olson (1957) provided a useful, En-glish-language review of this record (also see Olson, 1962; Olson
and Chudinov, 1992). Zone I is also called the Ocheriandinocephalian complex, and Zone II is the Isheevan dinocephaliancomplex. Zone III is now known to lack tetrapods, and Zone IVhas been called the pareiasaurian faunal complex.
Rubidge et al. (1995) reviewed the development of the SouthAfrican succession of Permian tetrapod assemblage zones origi-nally proposed by Broom (1906, 1907, 1909) and Watson (1914a,b). The current succession recognizes six assemblage zones ofMiddle-Late Permian age (fig. 2).
Thus, the current status of Permian global tetrapodbiochronology is that Romer’s scheme provides a threefold divi-sion of the Permian at the epoch level. Provincial tetrapodbiochronologies in Russia and South Africa provide a more de-tailed temporal subdivision of the Middle and Late Permian, butno such provincial biochronology exists for the Early Permian.However, an Early Permian tetrapod biochronology can be devel-oped based on the record in the western USA
Early Permian: Western USAThe most extensive Lower Permian tetrapod record is from the
western United States, especially from Texas, Oklahoma and NewMexico (e.g., Olson, 1967; Hook, 1989; Berman, 1993; Bermanet al., 1997). Recent stratigraphic revision of the Texas section(Hentz, 1988, 1989) considerably alters the stratigraphic nomen-clature long used here in the vertebrate paleontological literature.Hook (1989) placed the Texas Lower Permian tetrapod recordinto this revised lithostratigraphy but developed no biozonation(fig. 3). However, this record can be used to delineate three zones(fig. 3), though as Hook (1989) noted, some of the biostratigraphicdata here are weak because they rely on rare taxa or taxa of prob-lematic taxonomic status.
Records to the west from the Abo/Cutler/Sangre de Cristo for-mations of New Mexico and the Four Corners include Pennsylva-nian assemblages but mostly correlate to the lower WolfcampianBowie Group (Berman, 1993; Sumida et al., 1996). Youngerrecords in the western USA are of Leonardian age (Clear ForkGroup of Texas) and range to as young as early Guadalupian—Pease River Group of Texas and Duncan-Chikasha Formations ofOklahoma (e.g., Olson, 1962).
The tetrapod fossils from the Lower Permian of the westernUSA are the most complete record known. They should providethe basis for subdividing Early Permian time into at least threebiochronological units.
Middle-Late Permian: RussiaThe vast majority of the Russian Permian tetrapod localities are
between Kazan and the Ural Mountains in the drainage basins ofthe Kama and Belaya Rivers. Efremov (1937) first systematizedthis record, identifying four successive tetrapod “zones,” whichare of Middle-Late Permian age. However, Efremov’s (1937) third“zone,” his “pelycosaurian zone,” was later shown to not be basedon a fossil vertebrate assemblage between his second and fourthzones, so there no longer is a “Zone III.” Also, note that each ofEfremov’s “zones” are not actually zones (bodies of rock identi-fied by distinctive fossils) in the strict sense, but instead wereconceived by him to be “a comparatively long period of existenceof a given fauna” (Efremov, 1937, p. 124). Therefore, the Rus-sian “zones” really are biochronologic units that I would termfaunachrons or land-vertebrate “ages.”
“Zones” I and II are of Kazanian age and are separated from
18
“Zone” IV, of Tatarian age, by a substantial unconformity. The“Zone I” tetrapod assemblages include archegosaurids (Platyops,Melosaurus and Collidosuchus), the caseid pelycosaurPhreatophasma, several eotitanosuchians (Biarmosuchus,Eotitanosuchus, etc.), dinocephalians (Phreatosuchus,Estemmenosuchus) and the dicynodont Otsheria. “Zone II” as-semblages include archegosaurs (Platyops, Melosaurus, etc.),seymouriamorphs, captorhinomorphs (Hecatogomphus,Riphaeosaurus), pelycosaurs (Mesenosaurus and the caseidEnnatosaurus), theriodonts (Phthinosaurus, Titanophoneus, etc.),the dinocephalian Ulemosaurus and the dicynodont Venyukovia.The “Zone IV” assemblages are characterized by the dicynodontDicynodon and include the temnospondyls Dvinosaurus andChroniosuchus, the seymouriamorph Kotlassia, the pareiasaurScutosaurus, gorgonopsians, a therocephalian and a cynodont.
The Russian Middle to Late Permian record in large part paral-lels the South African record. However, the Russian record onlydelineates three zones, so its biostratigraphic resolution is onlyhalf that of the South African record, which includes six zones.
Middle-Late Permian: South AfricaThe Permian vertebrate record and its biostratigraphy in the
Karoo basin of South Africa has long provided the classic succes-sion of Middle to Late Permian tetrapod faunas. Recent reviewsby Rubidge (1995), Smith and Keyser (1995a, b, c, d) and Kitching(1995) recognize six successive zones based on tetrapods (fig. 4).These zones are characterized as assemblage zones, but theirboundaries lack explicit and consistent definition. This problemis best seen in the case of the Pristerognathus Assemblage Zone,stated by Smith and Keyser (1995b, p. 13) to be “an assemblagezone characterized by a therapsid fauna of low diversity domi-nated by Diictodon in association with Pristerognathus and theabsence of dinocephalian fossils that are a prominent componentof the fauna in the underlying zone.” However, only the lowestoccurrence of Ictidosuchoides corresponds to the base of the zoneand is not used to define its base. Precise definition of the SouthAfrican Permian assemblage zones is needed. Despite this prob-lem, the South African zonation provides the best global standardfor the subdivision of Middle and Late Permian time based ontetrapods.
Permian footprint biostratigraphyTetrapod footprints of Permian age are broadly distributed, be-
ing best known from the Lower Permian of western Europe andthe western USA (Haubold, 1971, 1984, 1996; Hunt et al., 1995;Lucas and Heckert, 1995). Other records include Russia(Tverdokhlebov et al., 1997; Lucas et al., 1998), the eastern USA-Canada (Cotton et al., 1995) and South America (Leonardi, 1994).Biostratigraphic zonation and correlation using the Permian foot-print record have only been developed in Western Europe (e.g.,Boy and Fichter, 1988; Ellenberger, 1983a, b, 1984). In NorthAmerica, the tracks have almost exclusively been used for paleo-ecological and paleoethological analyses (e.g., Lockley and Hunt,1995), and in other areas the track record is so limited as to be oflittle use for interpretive work.
Two problems hinder the use of Permian tetrapod footprints forbiostratigraphy and biochronology:
1. Ichnogenera of tetrapod footprints usually correspond to muchbroader taxonomic categories than do genera based on body fos-
sils. For example, the Late Carboniferous-Early Permianichnogenus Dimetropus corresponds to the body-fossil familySphenacodontidae. No particular sphenacodontid genus can beidentified by Dimetropus, so the temporal range of the ichnogenus= the temporal range of the Sphenacodontidae = Late Carbonifer-ous-Early Permian. Therefore, the ichnogenus only providesbiochronologic resolution on the order of epochs.
This is true of most, if not all, Permian tetrapod ichnogenera.For example, the ichnogenera Batrachichnus and Limnopus =Eryopoidea, Amphisauropus = Diadectidae, Dromopus =Araeoscelida, Tambachichnium = Diapsida, Dimetropus =Sphenacodontidae, Gilmoreichnus = Ophiacodontidae?,Ichniotherium = Edaphosauridae and Chelichnus = Synapsida(Haubold, 1996, table 3). These orders, superfamilies and fami-lies of body-fossil taxa have stratigraphic ranges on the magni-tude of series, so ichnobiostratigraphy based on the ichnotaxa canonly discriminate correlations at the series level.
2. The shape of a footprint is determined not only by the struc-ture of the foot skeleton of the trackmaker, but also by the interac-tion of the foot with the substratum. Much of this interaction andthe nature of the substratum affects footprint shape, and this hasbeen called extramorphological variation (Peabody, 1948). AsHaubold (1996, p. 23) succinctly observed:
Fragmentary tracks, incomplete trackways andother preservational variations of optimal trackmorphology and trackway pattern are of re-stricted taxonomic value. These areextramorphological features, mainly controlledby facies and sedimentological influences, andin comparison to the foot-morphology of thetrackmakers they are like chimeras. Taxa basedon such material are called phantom-taxa. Manyof the formerly described Permian footprints areproblematic in this regard.
Indeed, vastly oversplit ichnotaxonomies of Permian tetrapod foot-prints (examples are Holub and Kozur, 1981; Ellenberger, 1983a,b, 1984) have been used to develop biostratigraphic zonations,but these zonations lack a valid taxonomic basis and should beabandoned.
The prospects for a detailed Permian biostratigraphy andbiochronology based on tetrapod footprints are poor. In local ar-eas, ichnotaxa may provide a local biostratigraphy that reflectslocal facies changes (e.g., Conti et al., 1997), but this will only bea biostratigraphy as detailed as the facies changes.
ConclusionsTetrapods support the division of the Permian Period into three
epochs. The most extensive Permian tetrapod records are fromthe western U.S.A., the Russian Urals, and South Africa, and onlythese records are of global biostratigraphic and biochronologicsignificance at present. Tetrapod ichnogenera only provide a se-ries-level Permian biostratigraphy. A more precise global Per-mian tetrapod biochronology should be developed using a NorthAmerican standard for the Early Permian and a South Africanstandard for the Middle-Late Permian.
19
Figure 1. Map of Pangea showing principal Permian tetrapod localities. 1 = western USA; 2 = eastern USA (Dunkard); 3 = Scotland; 4 = Western Figure 1. Map of Pangea showing principal Permian tetrapod localities. 1 = western USA; 2 = eastern USA (Dunkard); 3 = Scotland; 4 = WesternEurope (Rotliegende); 5 = Russian Urals; 6 = Junggur basin, China; 7 = Ordos basin, China; 8 = Paraná basin, Brazil; 9 = Karoo basin, SouthAfrica; 10 = Morocco; 11 = southern Madagascar; 12 = Kashmir.
Figure 2. Previously proposed biostratigraphic/biochronologic schemes for Permian tetrapods. Note that this is not an exact correlation chartbecause of different workers’ perceptions of the relative age of some intervals.
20
Table 1. Brachiopod assemblages in the Selong Xishan section and their correlation with other faunas in the Peri-Gondwanan region.
21
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Conti, M. A., Mariotti, N., Nicosia, V. and Pittau, P. 1997.Succession of selected bioevents in the continental Permianof the southern Alps (Italy). Improvements in intrabasinaland interregional correlations; in Dickins, J. M., Yang, Z.,Yin, H., Lucas, S. G. and Acharrya, S. K., eds, Late Paleo-zoic and early Mesozoic circum-Pacific events and theirglobal correlation. Cambridge, Cambridge University Press,p. 51-65.
Cooper, M. R. 1982. A mid-Permian to earliest Jurassictetrapod biostratigraphy and its significance. ArnoldiaZimbabwe 9: 77-103.
Cotton, W. D., Hunt, A. P. and Cotton, J. E. 1995. Paleozoicvertebrate tracksites in eastern North America. New MexicoMuseum of Natural History and Science, Bulletin 6: 189-211.
Efremov, I. A. 1937. On the stratigraphic subdivision of thecontinental Permian and Triassic of the USSR on the basisof the fauna of early Tetrapoda. Doklady Akademiya NaukSSSR 16: 121-126.
Efremov, I. A. 1940. Preliminary description of new Permianand Triassic terrestrial vertebrates from the USSR. TrudyPaleontologicheskaya Instituta 10: 1-140.
Ellenberger, P. 1983a. Sur la zonation icnologique du Permienmoyen (Saxonien) du bassin de Lodève (Hérault). CompteRendus de l’Académie Science Paris Série II 297: 553-558.
Ellenberger, P. 1983b. Sur la zonation ichnologique du Permieninférieur (Autunien) du bassin de Lodève (Hérault). CompteRendus de l’Académie Science Paris Série II 297: 631-636.
Ellenberger, P. 1984. Donées complémentaires sur la zonationichnologique du Permien du Midi de la France (bassins deLodève, Saint Affrique et Rodez). Compte Rendus del’Académie Science Paris Série II 299: 581-586.
Haubold, H. 1971. Ichnia Amphibiorum et Reptiliorumfossilium. Encyclopedia of Paleoherpetology 18: 1-124.
Haubold, H. 1984. Saurierfährten. Wittenberg, Ziemsen-Verlag,
231 pp.Haubold, H.. 1996. Ichnotaxonomie und Klassifikation von
Tetrapodenfährten aus dem Perm. Hallesches JahrbuchGeowissenschaft 18: 23-88.
Hentz, T. F. 1988. Lithostratigraphy and paleoenvironments ofupper Paleozoic continental red beds, north-central Texas.Bowie (new) and Wichita (revised) Groups. The Universityof Texas at Austin, Bureau of Economic Geology, Report ofInvestigations 170, 55 pp.
Hentz, T. F. 1989. Permo-Carboniferous lithostratigraphy of thevertebrate-bearing Bowie and Wichita Groups, north-centralTexas; in Hook, R. W., ed., Permo-Carboniferous vertebratepaleontology, lithostratigraphy and depositional environ-ments of north-central Texas. Austin, Society of VertebratePaleontology, p. 1-21.
Holub, V. and Kozur, H. 1981. Revision einigerTetrapodenfährten des Rotliegenden und biostratigraphischeAuswertung der Tetrapodenfährten des obersten Karbon undPerm. Geologische Paläontologische Mitteilungen 11: 149-193.
Hook, R. W. 1989. Stratigraphic distribution of tetrapods in theBowie and Wichita Groups, Permo-Carboniferous of north-central Texas; in Hook, R. W., ed., Permo-Carboniferousvertebrate paleontology, lithostratigraphy and depositionalenvironments of north-central Texas. Austin, Society ofVertebrate Paleontology, p. 47-53.
Hunt, A. P., Lucas, S. G. and Lockley, M. G. 1995. Paleozoictracksites of the western United States. New MexicoMuseum of Natural History and Science, Bulletin 6: 213-217.
Kitching, J. W. 1995. Biostratigraphy of the Dicynodonassemblage zone. South African Committee for StratigraphyBiostratigraphic Series 1: 29-34.
Leonardi, G. 1994. Annotated atlas of South America tetrapodfootprints (Devonian to Holocene). Brasilia, ServicoGeológico do Brasil, 247 pp.
Lockley, M. G. and Hunt, A. P. 1995. Dinosaur tracks and otherfossil footprints of the western United States. New York,Columbia University Press, 338 pp.
Lucas, S. G. and Heckert, A. B., eds. 1995. Early Permianfootprints and facies. New Mexico Museum of NaturalHistory and Science, Bulletin 6, 301 pp.
Lucas, S. G., Lozovsky, V. R. and Shishkin, M. A. 1998.Tetrapod footprints from Early Permian redbeds of thenorthern Caucasus, Russia. Ichnos, in press.
Olson, E. C. 1952. The evolution of a Permian vertebratechronofauna. Evolution 6: 181-196.
Olson, E. C. 1957. Catalogue of localities of Permian andTriassic terrestrial vertebrates of the territories of the U. S.S. R. Journal of Geology 65: 196-226.
Olson, E. C. 1962. Late Permian terrestrial vertebrates, U.S.A.and U.S.S.R.. Transactions of the American PhilosophicalSociety, New Series 52: 1-223.
Olson, E. C. 1967. Early Permian vertebrates of Oklahoma.Oklahoma Geological Survey Circular 74: 1-111.
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Olson, E. C. and Chudinov, P. 1992. Upper Permian terrestrialvertebrates of the USA and Russia, 1991. InternationalGeology Review 34: 1143-1160.
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Peabody, F. E. 1948. Reptile and amphibian trackways from theMoenkopi Formation of Arizona and Utah. University ofCalifornia Publications, Bulletin Department of GeologicalSciences 27: 295-468.
Romer, A. S. 1966. Vertebrate paleontology. Third edition.Chicago, University of Chicago Press, 468 pp.
Romer, A. S. 1973. Permian reptiles; in Hallam, A., ed., Atlasof palaeobiogeography. Amsterdam, Elsevier, p. 159-167.
Rubidge, B. S. 1995. Biostratigraphy of the Eodicynodonassemblage zone. South African Committee for StratigraphyBiostratigraphic Series 1: 3-7.
Rubidge, B. S., Johnson, M. R., Kitching, J. W., Smith, R. M.H., Keyser, A. W. and Groenewald, G. H. 1995. An introduc-tion to the biozonation of the Beaufort Group. GeologicalSurvey of South Africa, Biostratigraphic Series 1: 1-2.
Smith, R. M. H. and Keyser, A. W. 1995a. Biostratigraphy ofthe Tapinocephalus assemblage zone. South AfricanCommittee for Stratigraphy Biostratigraphic Series 1: 8-12.
Smith, R. M. H. and Keyser, A. W. 1995b. Biostratigraphy ofthe Pristerognathus assemblage zone. South AfricanCommittee for Stratigraphy Biostratigraphic Series 1: 13-17.
Smith, R. M. H. and Keyser, A. W. 1995c. Biostratigraphy ofthe Tropidostoma assemblage zone. South African Commit-tee for Stratigraphy Biostratigraphic Series 1: 18-22.
Smith, R. M. H. and Keyser, A. W. 1995d. Biostratigraphy ofthe Cistecephalus assemblage zone. South African Commit-tee for Stratigraphy Biostratigraphic Series 1: 23-28.
Sumida, S. S., Berman, D. S. and Martens, T. 1996. Biostrati-graphic correlations between the Lower Permian of NorthAmerica and central Europe using the first record of anassemblage of terrestrial tetrapods from Germany.PaleoBios 17: 1-12.
Tverdokhlebov, V. P., Tverdokhlebova, G. I., Benton, M. J. andStorrs, G. W. 1997. First record of footprints of terrestrialvertebrates from the Upper Permian of the Cis-Urals,
Figure 4. South African assemblage zones of Middle-Late Permian tetrapods (after Rubidge et al., 1995) showing lowest stratigraphic occurrencesof genera for which the zones are named.
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Russia. Palaeontology 40: 157-166.Watson, D. M. S., 1914a, The zones of the Beaufort Beds of the
Karroo System in South Africa. Geological Magazine, NewSeries (6) 1: 203-208.
Watson, D. M. S. 1914b. On the nomenclature of the SouthAfrican pareiasaurians. Annals and Magazine of NaturalHistory 14: 98-102.
Spencer G. LucasNew Mexico Museum of Natural History
1801 Mountain Road N. W.Albuquerque, New Mexico 87104 USA
24
Graphic Correlation Applied to Lower PermianStratigraphic Sections of the Glass Mountains,West Texas
Stephen L. Benoist
IntroductionThe Wolfcampian through Leonardian stratigraphic interval of
the Glass Mountains, West Texas (Figs. 1, 2) historically has beenconsidered a standard of reference for Lower Permian strata ofNorth America (Ross, 1963b). Several researchers have suggestedthat the Leonardian Series, which is characterized by abundantand diverse marine fossils, would make a better international stan-dard of reference relative to the Artinskian and Kungurian stagesof the Russian platform, which have fewer well documented fau-nal elements. Although interest in the Lower Permian biostratig-raphy of the Glass Mountains continues, previous researchers havemade no attempt to objectively composite this biostratigraphicdata. Graphic correlation is a commonly used stratigraphic toolthat produces composite sections with a relatively high degree ofobjectivity (Edwards, 1982; Mann and Lane, 1995), and the pur-pose of the present paper is to briefly review an application ofgraphic correlation employing the existing Lower Permian bios-tratigraphic data of the Glass Mountains. Details of the graphiccorrelation process are given in Figure 4.
Graphic Correlation of Lower Permian Sections of theGlass Mountains
In the Glass Mountains, graphic correlation is facilitated by thefact that, although each biostratigraphic researcher has tended toconcentrate on a single taxon, in many cases they have recordedtheir taxon appearance data in sections measured along approxi-mately the same transect. Therefore, it has been possible to graphi-cally correlate these equivalent sections using lithologic horizonsas tie points. The sections thus composited include: 1) section 3of Ross (1960, 1962, 1963a), and the Split Tank sections of Coo-per and Grant (1972) and Wardlaw and Grant (1987); 2) Section24 of King (1931), which served as the standard reference section(SRS), and Section 4 of Ross (1960, 1962, 1963a); 3) Section 5of Ross (1962, 1963a), the Leonardian Lectostratotype of Cys(1977, 1981), and the Road Canyon Stratotype of Wardlaw andGrant (1987, 1989); and 4) Section 12 of King (1931) and Sec-tion 6 of Ross (1962, 1963a). For brevity, the process of litho-logic correlation of the above sections will not be discussed, al-though a detailed discussion of the process can be found in Benoist(1997). The locations of study sections are given in Figure 5.
After lithologic correlation, five rounds of graphic correlationwere applied to the study sections based on common first and lastfaunal appearance data among the sections (Fig. 6). Multiplerounds of correlation were necessary so that lines of correlation(LOCS) for each graphic correlation could be adjusted to fit dataadditions and adjustments produced by subsequent graphic corre-lations. The recorrelation process ceased after five rounds whenthe positions of LOCS stabilized.
In general, LOCs were placed to bisect the scatter of points ineach graph so that a maximum number of first appearances (FAs-white squares in Figure 6) lie along or below the LOC, and amaximum number of last appearances (LAs- black squares in Fig-ure 6) lie along or above the LOC. In addition, although biostrati-
graphic data from conodont, ammonoid, and brachiopod researchwere included in this study, the placement of LOCs was weightedto conform with fusulinacean appearances. This decision wasbased on the fact that, among the study taxa, fusulinaceans: 1)occur in all the study sections, 2) exhibit multiple levels of ap-pearance and a consistent stratigraphic order within sections, and3) display a level of taxonomic consistency because the majorityof fusulinacean taxa in this study were described by a single re-searcher (Ross 1960, 1962, 1963a, 1964).
Apparent anomalies in data point distribution occur in the graphsof the CS versus the Section 3 and the Leonard Mountain com-posite sections (Fig. 6- A and D respectively). In the graph of theCS versus the Section 3 composite, numerous brachiopod LAs(unlabelled black squares in the vertical x-axis interval between514 to 525 units) occur well below the LOC, which has been po-sitioned to parallel the linear trend in fusulinacean appearances;therefore, during compositing, these LAs will undergo large up-ward range extensions to the level of the LOC. The lack of con-formity between the brachiopod and fusulinacean data patternsreflects the relatively sporadic appearance of brachiopods amongthe study sections, with the LAs of these taxa tending to be trun-cated in the CS relative to the Section 3 composite. Conversely,the vertical alignment of brachiopod FAs (unlabelled white squaresat approximately 492 on the x-axis) below the LOC indicates thatthe FAs of these taxa are truncated in the Section 3 compositerelative to the CS. In the graph of the CS versus the LeonardMountain composite, several taxon FAs occur well above the LOC(x-axis interval between 0 to 400 units) and do not conform to thefusulinacean data pattern; therefore, during compositing, these FAswill undergo large downward range adjustments to the LOC level.This anomaly results from the fact that CS FAs of these taxa werefirst established by studies (Cooper and Grant, 1972; Wardlawand Grant, 1987) in which sampling was limited to the relativelythin Cathedral Mountain Formation in the Split Tank area (Fig.7); therefore, the LOC suggests that these anomalous CS FAs arehighly truncated.
ResultsThe end product of this study is a Glass Mountains composite
standard (CS) that contains the complete biostratigraphic data set(795 taxa) for Wolfcampian through Roadian strata of the GlassMountains study sections. Also, the CS contains any extensionsof taxon ranges that occurred during graphic correlation (See Fig-ure 4 for details of the range extension process). Listed in orderof decreasing numbers of species in the CS, the CS taxa belongprimarily to four groups: brachiopods, fusulinaceans, conodonts,and ammonoids. Within these groups, taxon range limits have aninherent level of uncertainty; and, among the study sections, indi-vidual taxa exhibiting the largest number of appearances shouldhave ranges closer to true stratigraphic ranges (Shaw, 1964). Also,many taxon ranges in the CS are probably underestimates. Thisprobability derives primarily from two factors: 1) the facies-con-trolled distribution of most species employed in this study, and 2)the restriction of data recovery to measured stratigraphic sections.In the case of ammonoid and brachiopod appearance data, thesecond factor is accentuated because many of the existing appear-ance data are recorded at map localities and are not placed inmeasured stratigraphic sections (A comprehensive summary ofPermian biostratigraphic data of the Glass Mountains, inclusiveof appearances not placed in measured stratigraphic sections, is
25
Figure 1. Location of the Glass Mountains, West Texas (from Kozur and Mostler, 1995)
Figure 2. Permian eustasy curve with series and stages for southwestern North America, Ural region and Tethyan region. Checks indicate unitspresent in the Glass Mountains (modified after Ross, 1964).
26
Figure 3. Lateral stratigraphic relationships in the Glass Mountains (from Cys, 1981).
Figure 4. Graphical comparison between a hypothetical standard reference section (SRS) and a temporally comparable (CS). Taxa A, B, C, and Dare common to both sections and their bases (O) and tops (+) plot as points on the graph. The line of correlation (LOC) fits the scatter of points sothat the line follows the “tunnel” created among the bases and tops of A, B, and C. In the case of taxon D, the position of its base above and its topbelow the LOC indicates that both the base and top of taxon D’s range need adjustment in the SRS. The adjustment of range is achieved byprojecting the base and top of D’s range on the graph into the LOC. The horizontal projections of the LOC intersection points become taxon D’snew range limits in the SRS. Taxon E, which occurs only in the CS, enters the SRS through the same procedure, with the horizontal projections oftaxon E’s intersection points with the LOC becoming new range data in the SRS.
27
Figure 5. Location of Glass Mountains stratigraphic sections used in the present study (Modified after Ross, 1962, 1963a).
presented by Wardlaw, 1996).The ranges of CS taxa are summarized in Figure 8. In this range
chart, only those taxa ranges that are important in the delineationand subdivision of the Leonardian Series (Artinskian-Kungurianstages) are illustrated (Discussion of the criteria used to producethe zonation presented herein can be found in Benoist, 1997). Also,resulting from factors discussed in the previous paragraph, theuncertainty attaining to taxon ranges is illustrated by: 1) placingrelatively wide gray lines between biostratigraphic subdivisions,2) noting after each taxon’s name its total number of appearances,and 3) indicating those CS taxon ranges that conflict significantlywith published zonal schemes within the southwestern UnitedStates.
ConclusionIn the Glass Mountains, graphic correlation was facilitated for
the reasons that all study sections 1) extend through the studyinterval and are in objective stratigraphic position relative to theoverlying Guadalupian Series, 2) are dominated throughout theirextent by rocks representative of marine paleoenvironments, and3) have a comparable fauna that contains abundant representa-tives of rapidly evolving and wide ranging marine groups such asconodonts, fusulinaceans, and ammonoids. Furthermore, speciesdescriptions and range data for key conodont and fusulinaceantaxa were obtained primarily from Wardlaw and Grant (1987,1989) and Ross (1960, 1962, 1963a) respectively; therefore, thesetaxa were consistently described among the study sections.
The CS produced in this study combines the biostratigraphicdata of the study sections into a single section and incorporatesany taxon range extensions produced during the graphic correla-tion process. Therefore, the CS serves as a better standard ofreference for Glass Mountains Leonardian strata than any one ofthe study sections. Negative factors are that: 1) the Glass Moun-tains SRS and other study sections contain major breaks in rockaccumulation (Ross, 1987; Ross and Ross, 1994), 2) only bios-tratigraphic data from measured stratigraphic sections could be
correlated, 3) taxa distributions are strongly facies controlled, and4) many of the Glass Mountains sections are not accessible toscientific researchers, although the type area for the LeonardianSeries (Lectostratotype of Cys (1977, 1981)) remains open toqualified researchers.
ReferencesBenoist, S. L., 1997, Application of graphic correlation to upper
Lower Permian (Artinskian-Kungurian) stratigraphicsections of the Glass Mountains, West Texas and the westernslope of the Ural Mountains, Russia (Ph.D. thesis]: IowaCity, Iowa, The University of Iowa, ~241p.
Cooper, G. A., and Grant, R. E., 1972, Permian Brachiopods ofWest Texas, Part I: Smithsonian Contributions toPaleobiologv, no. 14, p. 1-230.
Cys, J. M., 1977, Lectostratotype of North America LeonardianSeries, Glass Mountains, West Texas (abs.): GeologicalSociety of America Abstracts with Programs, v. 9, p. 14.
Cys, J. M., 1981, Preliminary report on proposed Leonardianlectostratotype section, Glass Mountains, West Texas:Symposium and Guidebook, 1981 Field Trip, PermianBasin Section, Society of Economic Paleontologists andMineralogists, p. 183-205.
Edwards, L. E., 1982, Quantitative biostratigraphy: the methodshould suit the data: in Cubitt. J. M., and Reyment, R. A.,eds., Quantitative Stratigraphic Correlation, John Wileyand Sons, p. 45-60.
King, P. B., 1931, Geology of the Glass Mountains, Texas; partI, Descriptive geology: University of Texas Bulletin, 3038,167p.
Kozur, H., and Mostler, H., 1995, Guadalupian (MiddlePermian) conodonts of the sponge-bearing limestones fromthe margins of the Delaware Basin, West Texas: GeologiaCroatica, v. 48/2, p. 107-128.
Mann, K. O., and Lane, R. H., 1995, Graphic correlation: apowerful stratigraphic technique comes of age: in, Mann, K.
28
A
Figure 6. Fifth round graphic correlations of the Composite Standard versus: A- Section 3 composite, B- Section 2, C- Section 7, D- LeonardMountain composite.
29
D
B. C.
D. cont.
Figure 6: continued
30
Figure 7. Lithologic correlation of the upper portion of Section 3 (Ross, 1960, 1962, 1963a) and the Split Tank sections of Cooper and Grant(1972), and Wardlaw and Grant (1987).
O., Lane, R. H., and Scholle, P. A., eds., Graphic Correla-tion, SEPM Society for Sedimentary Geology SpecialPublication No. 53, p. 3-13.
Ross, C. A., 1960, Fusulinids from the Hess Member of theLeonard Formation, Leonard Series (Permian), GlassMountains, Texas: Contributions from the CushmanFoundation for Foraminiferal Research, v. 11, Pt. 4, p. 117-133.
Ross, C. A., 1962, Fusulinids from the Leonard Formation(Permian), western Glass Mountains, Texas: Contributionsfrom the Cushinan Foundation of Foraminiferal Research:v. 13, Pt. 1, p. 1-21.
Ross,C. A., 1963a, Fusulinids from the Word Formation(Permian), Glass Mountains, Texas: Contributions from theCushman Foundation for Foraminiferal Research, v. 14, Pt.1, p. 17-31.
Ross, C. A., 1963b, Standard Wolfcampian Series (Permian),Glass Mountains, Texas: Geological Society of AmericaMemoir 88, 205 p.
Ross, C. A., 1964, Two significant fusulinid genera from the
Word Formation (Permian), Texas: Journal of Paleontology,v. 38, p. 311-315.
Ross, C. A., 1987, Leonardian Series (Permian) , GlassMountains, West Texas, in, Cromwell, C., and Mazzullo, L.,eds., The Leonardian facies in W. Texas and S.E. NewMexico and guidebook to the Glass Mountains, West Texas:1987 Permian Basin Section Society of Economic Paleon-tologists and Mineralogists Publication 87-27, p.
Ross, C. A. , and Ross, J. R. P. , 1994, Permian sequencestratigraphy: in, Scholle, P. A., Peryt, T. M., and Ulmer-Scholle, D. S., eds., The Permian of Northern Pangea, Vol.1, Springer-Verlag, Berlin, Heidelberg, New York, p. 98-123.
Shaw, A. B., 1964, Time in Stratigraphy: McGraw Hill, NewYork, 365p.
Wardlaw, B. R., 1996, Range charts for the Permian of WestTexas: in, Guadalupian II, Abstracts and Proceedings of theSecond International Guadalupian Symposium, Sul RossUniversity, Alpine, Texas, p. 40-60.
Wardlaw, B. R., and Grant, R. E., 1987, Conodont biostratigra-
31Figure 8: Range chart for selected taxa in the Glass Mountains CS with proposed stages and substages.
32
Figure 8: continued
phy of the Cathedral Mountain and Road Canyon forma-tions, Glass Mountains, West Texas: in, Cromwell, D., andMazzullo, L. J., eds., The Leonardian facies in West Texasand Southeast New Mexico and guidebook to the GlassMountains, West Texas: 1987 Permian Basin Section,Society of Economic Paleontologists and MineralogistsPublication 87-27, p. 63-66.
Wardlaw, B. R., and Grant, R. E., 1989, Conodont biostratigra-phy of the Permian Road Canyon Formation, Glass Moun-tains, Texas: United States Geological Survey Bulletin 1895,Shorter Contributions to Paleontology and Stratigraphy, p.Al-Al8.
Stephen L. Benoist10461 Remington Lane
Dallas,TX 75229(972) 406-8343
Graphic Correlation of Upper Carboniferous-Lower Permian Strata of Spitsbergen and theLoppa High, Barents Sea Shelf
R. M. Anisimov, V. I. Davydov, I. Nilsson
IntroductionGraphic correlation (GC) is a semiquantitative biostratigraphic
correlation technique that uses total fossil content of sections toprovide refined correlation. Whereas other biostratigraphic meth-ods provide correlation at the zonal scale, graphic correlation en-ables correlation within zones. Values for the relative sedimenta-tion rates can be estimated even for short intervals and the posi-tion of unconformities can be estimated with a fair degree of ac-curacy. Consequently, graphic correlation is a valuable tool forcorrelating unconformities and estimating the duration of hiatuses.Moreover, graphic correlation can be used to predict the presenceof a hiatus or a series of diastems in unsampled or poorly sampledintervals. In addition, with zonal boundaries represented on thegraph, graphic correlation can be used to adjust the position ofzone boundaries in a local section.
The present study is based on Upper Carboniferous-Lower Per-mian (upper Moscovian - Sakmarian) successions from Spitsbergen(fig. 1) and from a well drilled in upper Paleozoic strata of theLoppa High on the Barents Sea. Fusulinid biostratigraphy of theSpitsbergen localities was established by Nilsson (1988, 1993)and Nilsson & Davydov (1992); these authors recognized a seriesof breaks in the sedimentary succession but the precise durationwas not established.
Sampling density is important in graphic correlation because
33
Figure 1. Location of studied sections showing structural elements
34
the last and first occurrence of taxa define the line of correlation(LOC). Due to sampling gaps in our data, certain important strati-graphic intervals, where graphic correlation indicates the occur-rence of substantial sedimentation changes, remainuncharacterized. These are referred to as "intervals of reducedthickness." This term indicates that a non-sampled interval, al-though corresponding to a relatively long period of time on thebiostratigraphic scale, is represented by a short interval on thegraph. Such features either may be linked to relative sea levelrise, deepening of the basin, and the formation of condensed sec-tions (not the case in Spitsbergen), or, they could indicate hiatusesor diastems associated with sea level fluctuations.
MethodologyThe methodology used in this project is based on the technique
introduced by Shaw (1964) and summarized by later authors (e.g.,Miller, 1977; Edwards, 1984, 1989). A recent and comprehen-sive discussion on the principles and applications of graphic cor-relation was presented by Mann and Lane (1995).
In addition to species ranges, we utilized generic ranges, espe-cially where specific data were not available. The stratigraphicranges of genera, although longer than those of their componentspecies and less useful in determining the LOC, do provide addi-tional data points on the graph and are useful in correlation ofsections with inadequate sampling.
Bases of fusulinid zones were used for correlation and providedrelative time indicators on the graph. The biostratigraphic scalewith fusulinid zones and their respective numbers are presentedin Figure 2.
Generally the LOC (line of correlation is positioned so that rangetops plot to the left and range bases plot to the right of the LOC,and the number of adjustments of taxonomic ranges is minimal;that is the data points form as tight a cluster around the LOC aspossible.
The alignment of data points at a particular stratigraphic levelsuggests the presence of hiatus or a condensed section.
AbbreviationsLOC: Line of correlation. The LOC is defined by an infinite
number of time-equivalent points common to the sections beingcompared. The position of the LOC is controlled by the data pointson the graph. The LOC is drawn as straight line, ignoring the fre-quent, minute changes in sedimentation pattern that produce so-called depositional noise because it shows general pattern of sedi-mentation.
RRS: Relative rate of sedimentation. The RRS is reflected bythe slope of the LOC and indicates how much rock had accumu-lated in the two sections during the same time intervals. The sedi-mentation rate in the composite section equals 1.0. If the rate ofsedimentation is greater in the comparison section than in the com-posite section, the RRS will be greater than 1.0; if the rate is lowerit will be less than 1.0.
RSL: Relative sea level. RSL changes may indicate eustatic (glo-bal) or local (tectonic) transgression-regression events, with RSLlows and highs corresponding to hiatuses and condensed sections,respectively.
Geologic History Of The Spitsbergen Region As InferredFrom Graphic Correlation
The Spitsbergen localities and, to a lesser degree, the Loppa
High share a common geologic history (fig. 2) as could be ex-pected from their proximity. Sedimentation in the region appearsto have been controlled by local tectonic events superimposed oneustatic sea level changes.
The relative span of hiatuses in the sections and their corre-spondence to one another were employed to develop the relativesea-level curve (fig. 2). The following succession of major trans-gression-regression events were recognized:
Late Moscovian time (zones 21 and 22) in the Loppa High cor-responds to an intermediate, to highstand of relative sea level anda high RRS roughly equal to 4 or 5. (fig. 8). The lower Kasimovianhiatus (zone 23 and possibly part of 24) in well BG-1, KolguevIsland (Barents Sea shelf) (Davydov, 1997) suggests a loweringof RSL. However, the corresponding hiatus in Spitsbergen oc-curs only in Skansen (fig. 4). Therefore, the RSL change does notappear to be eustatic in origin. Data from Skansen, which is inter-preted to be a maximum flooding surface (probably due to itshigh paleotopographic position), indicates a short-term transgres-sion during lower Kasimovian, corresponding to the boundarysuccession of zones 23/24.
Upper Kasimovian-lower Gzhelian time (zones 25 through 27)corresponds to a RSL highstand with maximum flooding in earli-est Gzhelian. The corresponding strata is not present (except forthe basal part of zone 27) only in Skansen section, probably dueto erosion.
The hiatus spanning the upper part of lower Gzhelian and middleGzhelian (upper part of zone 27 and zone 28) in the Trollfuglfjella(Fig. 3) and Skansen sections, and possibly in Kolosseum (fig. 7)and Boltonbreen (fig. 6), corresponds to an intermediate to lowRSL.
The upper Gzhelian (zone 29) corresponds to intermediate tohigh RSL; only the Skansen locality is missing this stratigraphicinterval.
The lower Orenburgian (zone 30) is missing in all Spitsbergensections, although data from Kolosseum locality is inconclusive.
Remnant middle Orenburgian strata (zone 31) are present in theTrollfuglfjella and Boltonbreen sections, and they are assumed tobe preserved in Kolosseum locality. Therefore, this stratigraphicinterval is interpreted to represent a short-term transgression withintermediate to high RSL.
The stratigraphic interval encompassing the upper part of themiddle to the uppermostOrenburgian (upper part of zone 31 to the uppermost part of zone32) corresponds to an extensive hiatus that occurs in all ofSpitsbergen localities that is interpreted as a major regression event.
Sedimentation resumed in latest Orenburgian and appears to becontinuous across the C/P boundary, extending to the middle oflower Asselian (up to the middle part of zone 33). Unusually highand uniform RRS during this stratigraphic interval is interpretedin all Spitsbergen sections including Tyrrellfjellet where this strati-graphic interval is densely sampled (Fig. 5). RRS range from 3 to13 and suggest a major transgression during latest Orenburgian-early Asselian time. These interpretations are consistent with pre-liminary graphic correlation of well # X (Loppa High) where RRSwithin this stratigraphic interval equals approximately 8.0.
The middle Asselian stage (zones 34 through 36) correspondsto an intermediate to low position of RSL. This stratigraphic in-terval apparently is absent in Skansen with only the basal or someother part of zone 35 preserved. The corresponding strata in therest of the Spitsbergen sections are not sampled. Nonetheless, the
35
WE
LL
X
Figure 2. Correlation chart of studied sections in Spitsbergen and the Loppa High with the interpreted relative sea level curve. Horizontally stripedareas represent intervals of reduced thickness due to diastems; diagonally-striped areas represent hiatus.
36
Figures 3 - 8. Graphic correlation of sections from Spitsbergen and the Loppa High, Barents Sea. Crosses indicate tops, and circles bases ofpecies. Triangles indicate tops, and squares bases of genera. 3: Trollfuglfjella section. 4: Skansen section. 5: Tyrrellfjellet section. 6:Boltonbreensection: 7: Kollsseum section. 8: well - X : Loppa High.
37
positions of data points, constraining the LOCs immediately be-low and above the interval, indicate major changes in sedimenta-tion pattern and are tentatively called "intervals of reduced thick-ness." This term suggests either a pronounced hiatus somewherewithin the middle Asselian or a number of short hiatuses (diastems).The same interpretation appears to be valid for the well #X (LoppaHigh). However, the presence of part of zone 35 in the Skansensection suggests a major, though short-term, transgression withinzone 35.
A major transgression during Late Asselian (from zone 37 orthe uppermost part of zone 36) is suggested by the relatively highRRS in the Trollfuglfjella and Skansen sections (1.5 and 2 respec-tively) and, probably well # X where the RRS, interpreted frompoorly constrained LOC, equals 5. However, biostratigraphic datafrom these sections are poor and the Sakmarian stage is eitherpoorly defined paleontologically or not defined at all in theSpitsbergen localities. In addition, data from the Kolosseum sec-tion, where the LOC suggests uniform sedimentation from zone37 to the Asselian-Sakmarian boundary, contradict the notion of amajor latest Asselian transgression because of a low RRS (0.27).
Therefore, there are two possible scenarios for the sedimenta-tion pattern during latest Asselian-early Sakmarian time. If theinterpretations for Trollfuglfjella and Skansen sections, and well# X are correct, the low RRS in Kolosseum could best be ex-plained by a local tectonic event involving a short-scale uplift ofthe tectonic block. Alternatively, there is evidence for a hiatusspanning the lower part of zone 37 in Trollfuglfjella and Kolosseumsections. If this turns out to be correct, the LOC position inKolosseum section should have a different slope indicating higherRRS with the alignment of data points at 166 m-level correspond-ing to the hiatus spanning the lower part of zone 37.
ConclusionsI. Sea-level changes: relative versus eustatic
It is difficult to distinguish between eustatically driven and tec-tonically driven sedimentation changes. The Spitsbergen sectionsare located 60 km apart and it is difficult to correlate the RSLcurve drawn for these locations to the global sea-level curve. Mostsignificantly, major RSL changes do not coincide with the bound-aries of the relative time scale. There is no "basal" Asselian trans-gression in Spitsbergen, rather there is continuous sedimentationacross the C/P boundary interval. A major transgression begins inlatest Orenburgian time. Similarly, there is no apparent hiatus atthe Asselian-Sakmarian boundary and transgression begins in thelate Asselian; however, these data, derived only from graphic cor-relation of the Kolosseum section, are regarded as tentative.
Naturally, the hiatuses are related to RSL lowstands and corre-lation of sedimentation breaks over great distances could help dis-tinguish local from eustatic sea-level changes. At this point, atleast some hiatuses identified in Spitsbergen can be tracedinterregionally. The preliminary correlation of Spitsbergen lo-calities and sections in Darvas region of Pamirs (Middle Asia),separated by 5000 km, indicates the presence of the prominentmiddle Gzhelian (zone 28) and middle-upper Orenburgian (theupper part of zone 31 to the uppermost part of zone 32) hiatuses.
ReferencesAnisimov, R. M., and Davydov, V. I., 1998, Graphic Correlation
of Upper Carboniferous-Lower Permian strata inSpitsbergen, Norwegian Arctic: Abstracts of the Fortieth
Annual Meeting of Idaho Academy of Science, J. of I. A. ofScience, v. 34, p. 31
Davydov, V. I., 1997b, Fusulind biostratigraphy of the UpperPaleozoic of Kolguev Island and Franz Josef Land: Interna-tional Symposium "Biostratigraphy of Oil-Gas bearingBasins", St. Petersburg: 40-59 (In Russian and English).
Edwards, L. E., 1984, Insights on why Graphic Correlation(Shaw's method) works: Journal of Geology, v. 93, p.583-597
Edwards, L. E., 1989, Supplemental Graphic Correlation: apowerful tool for paleontologists and non-paleontologists:Palaios, v. 4, p.127-143
Mann, K. and Lane, R., eds, 1995, Graphic Correlation, SEPMspecial publication # 53, 263 p.
Miller, F. X., 1977, The Graphic Correlation method in bios-tratigraphy, in Kauffman, E. and Hazel, J., eds., Conceptsand Methods of Biostratigraphy: Stroudsburg, DowdenHutchinson and Ross, p. 165-186
Nilsson, I., 1988, Carboniferous and Permian fusulinids on theNordfjorden Block, Spitsbergen (Svalbard): UnpublishedMs. Thesis, University of Oslo, 143 p.
Nilsson, I., 1993, Upper Paleozoic fusulinid stratigraphy of theBarents Sea and surrounding areas: Dr. Sci. Thesis, Univer-sity of Tromso, 538 p.
Nilsson, I. and Davydov, V., 1992, Middle Carboniferous-LowerPermian fusulinid stratigraphy in central Spitsbergen, ArcticNorway. IKU Report 23.1356.00/07/92, 175p.
Shaw, A. B., 1964, Time in Stratigraphy: New York, McGraw-Hill Book Co., 365 p.
Stemmerik, L. and Worsley, D., 1995, Permian history of theBarents shelf area, in Scholle, P., Peryt, T. and Ulmer-Scholle, D., eds., The Permian of Northern Pangea, v. 2, p.81-97
Worsley D. et al., 1986, Evolution of an arctic archipelago; thegeological history of Svalbard: Den Norske StatsOljeselskap, Stavanger, 120 p.
R. M. AnisimovPermian Research Institute
Department of Geosciences Boise State University
1910 University Drive, Boise, ID, [email protected]
V. I. DavydovPermian Research Institute
Department of Geosciences Boise State University
1910 University Drive, Boise, ID, 83725
I. NilssonSaga Petroleum ASA
N-1301 Sandvika, [email protected] 49
38
Carboniferous and Permian Stratigraphy of theBaoshan Block, West Yunnan, Southwest China
Wang Xiang-dong, Tetsuo Sugiyama andKatsumi Ueno
The Baoshan Block is one of the key areas for understandingGondwana dispersion and Asian accretion. The present contribu-tion is intended to provide an improved framework for the Car-boniferous and Permian stratigraphy of the Baoshan Block basedon recent cooperative studies between Chinese and Japanese re-searchers.The Lower Carboniferous sequence in the Baoshan Block includestwo distinct sedimentary facies: a shallow-marine carbonate plat-form facies and a basinal facies. The former is subdivided intothe Yudong, Shihuadong, and Yunruijie formations, in ascendingorder, which are widely distributed in the block.
The Yudong Formation consists of shale and mudstone. It wasdated as late Tournaisian by conodonts such as Gnathoduspunctatus and Doliognathus latus (Li and Duan, 1993), by coralssuch as Zaphrentites parallelus and Commutia szulczewskii (Wanget al., 1993), and by brachiopods such as Lamellosathyrislamellosa, Spinocyrtia laminosa, Sprifer tomacensis, Schuchertellamagna, and Dictyoclostus triznae (Jin and Fang, 1983). TheDazhaimen Formation, which disconformably underlies theYudong Formation, yields abundant late Devonian conodonts, in-cluding Palmatolepis wolskjae, Bispathodus costatus, andPalmatolepis triangularis. Therefore, the disconformity betweenthese two formations indicates a distinct hiatus representing latestDevonian and earliest Carboniferous time.
The Shihuadong Formation, which conformably overlies theYudong Formation, consists mainly of mudstone, and dolomiticand argillaceous limestone with chert nodules. The boundary be-tween the Tournaisian and Visean is defined by the first occur-rence of Gnathodus texanus in the lower part of the formation.Very abundant dissepimental corals, such as Siphonophyllia,Keyserlingophyllum, Cyathoclisia, Palaeosmilia,Kueichouphyllum, and Siphonodendron occur in the middle andupper parts of this formation.
The Yunruijie Formation is characterized by oolitic grainstoneand bioclastic grainstone. It yields the dissepimental coralsDiphyphyllum carinatum, Dibunophyllum sp. and Palaeosmiliasp. and smaller foraminifers, which indicate a late Visean age.
The Lower Carboniferous basinal facies in the Baoshan Blockis composed of the Qingshuigou Formation and overlyingJiangjiawan Formation in ascending order. The Qingshuigou For-mation consists of dark lime-mudstone and wackstone containingthe conodonts Polygnathus bischoffi, Gnathoduspseudosemiglaber, and Mestognathus beckmanni (Wang et al.,1993), the ammonoids Merocanites (Michiganites) bicarinatus,Bollandites bashatchensis, and Dzhaprakoceras deflexum (Liangand Zhu, 1988), and the non-dissepimented corals Pentaphyllumhibernucum and Rotiphyllum sp. (Wang et al., 1993). This faunalassociation indicates a late Tournaisian to early Visean age. TheJiangjiawan Formation conformably overlies the QingshuigouFormation, and is composed of mudstone with iron nodules andshales in the lower part. It yields abundant small, non-dissepimented rugosan species of Pentaphyllum, Ufimia,Commutia, Sychnoelasma, and Zaphrentites, and some conodonts,
such as Gnathodus semiglaber and G. pseudosemiglaber. The up-per part of the formation is characterized by the alternation ofmudstone containing small solitary corals, and sandstone.
The Lower Carboniferous strata of the block are unconformablyoverlain by the Lower Permian Dingjiazhai Formation. A deposi-tional break encompassing Serpukhovian to probable Asselian iswidely recognized in the Baoshan Bolck. The Dingjiazhai For-mation is mainly composed of clastics with diamictites in the lowerpart. These diamictites are considered by some authors to be glacio-marine in origin (e.g., Jin, 1994). In the upper part of the forma-tion, there are a few limestone intercalations containing abundantbrachiopods, bryozoans, and crinoids (BBC communities). Chen(1984) first reported fusulinaceans, including Triticites ohioensis,T. pusillus, T. parvulus, and Hemifusulina maoshanensis, fromthese limestones and considered the age of the Dingjiazhai For-mation to be Late Carboniferous. Until recently, a Late Carbonif-erous age has been accepted for the formation (Fang and Fan,1994; Jin, 1994). However, according to our preliminary exami-nation of foraminifers from limestone intercalations in the typesection, the fauna includes Pseudofusulina sp., Eoparafusulina spp.,Boultoniidae n. gen.?, and Pachyphloia sp. We prefer to considerthe age of the fauna as Early Permian (probably Sakmarian). Thisconclusion is coincident with the assessment of the brachiopodfauna by Shi et al. (1995). In addition, several small solitary non-dissepimented corals, including Cyathaxonia sp., Plerophyllumsp., and Hapsiphyllidae n. gen.? were found in these limestoneintercalations. These corals have often been referred to as theCyathaxonia fauna, which inhabited stressed environments.
The Woniusi Formation comprises thick basaltic lava sheets andsome tuffaceous intercalations. It lies on the Dingjiazhai Forma-tion without a distinct hiatus in the Dongshanpo and Dingjiazhaiareas. Formerly, it was also dated as late Carboniferous, based onthe occurrence of Triticites from the limestone intercalations in itslower part. However, as a result of our field investigation at thetype section of the formation, we consider these limestone inter-calations, together with associated clastics, to be faulted repeti-tions of the underlying Dingjiazhai Formation.
The Bingma Formation rests on the Woniusi Formation in DaaoziVillage. It is characterized by volcaniclastic conglomerate withseveral thin lava intercalations in the lower part, and red and purplesiltstone and mudstone in the upper part. No fossils have beenfound in the type area.
The Shazipo Formation is the uppermost stratigraphic unit ofthe upper Paleozoic in the Baoshan Block. It consists of wackstoneand bioclastic grainstone in the lower part, dolomitic limestone inthe middle part and dolostone in the upper part. Foraminifers(Eopolydiexodina afghanensis, Neoschwagerina sp., Verbeekinasp., Shanita amosi) and massive corals (Ipciphyllum sp.) have beenreported from this formation (Sheng and He, 1983; Fang and Fan,1994; Zhang, 1996). In addition, we have found Wentzelophyllumpersicum, Wentzelella shidianenses and a probable new genus ofthe family Staffellidae. The fauna is slightly different from thetypical Tethyan faunas observed in South China and Indochina.The Shazipo fossils indicate that the age of the formation is possi-bly late Chihsian to early Lopingian.
To sum up, the Carboniferous and Permian stratigraphy (Figure1) of the Baoshan Block can be closely compared with that of theSibumasu Block, which is considered to be one of the Gondwana-derived terranes in present-day Southeast Asia.
39Figure 1. Carboniferous - Permian stratigraphic framework of the Baoshan block.
40
ReferencesChen G. B., 1984, The Carboniferous of the Baoshan area, West
Yunnan. Jour. Stratigr. (China), 8(2): 129-135. (in Chinese)Fang R. S. and Fan J. C., 1994, Middle to Upper Carboniferous-
Early Permian Gondwana facies and palaeontology inwestern Yunnan. Yunnan Science and Technology Press,Kunming. 121p. (in Chinese with English abstract)
Jin X. C., 1994, Sedimentary and paleogeographic significanceof Permo-Carboniferous sequences in Western Yunnan,China. Geologisches Institit der Universitaet zu KoelnSonderveroeffentlichungen, 99: 1-136.
Jin Y. G. and Fang R. S., 1983, Early Carboniferous brachio-pods from Shidian, Yunnan. Acta Palaeontologica Sinica,22(2): 139-151. (in Chinese with English abstract)
Li R. J. and Duan L. L, 1993, Early Carboniferous conodontsequence in the Baoshan-Shidian area, Yunnan and itsstratigraphic significance. Acta MicropalaeontologicaSinica, 10(1): 37-52. (in Chinese with English abstract)
Liang X. L. and Zhu K. Y., 1988, Early Carboniferous cephalo-pods of Baoshan, Yunnan. Acta Palaeontologica Sinica,27(3): 288-301. (in Chinese with English abstract)
Sheng J. Z. and He Y., 1983, Permian Shanita ? Hemigordius(Hemigordiopsis) (Foraminifera) fauna in western Yunnan,China. Acta Palaeontologica Sinica, 22(1): 55-61. (inChinese with English abstract)
Shi G. R., Archbold, N. W. and Fang Z. J., 1995, Thebiostratigraphical and palaeogeographical significance of anEarly Permian brachiopod fauna from the DingjiazhaiFormation, Baoshan Block, Western Yunnan, China.Proceedings of the IGCP Symposium on Geology of SEAsia, Hanoi, XI/1995. Jour. Geology, Ser. B, 5/6, 63-74.
Wang X. D., Zhu K. Y. and Chen Z. T., 1993, The LowerCarboniferous of Baoshan, Yunnan. Jour. Stratigr. (China),17(4): 241-255. (in Chinese with English abstract)
Zhang, Y. Z. (ed.), 1996, The lithostratigraphy of Yunnan. ChinaUniversity of Geoscience press,Wuhan, 370p. (in Chinese)
Wang Xiang-dongNanjing Institute of Geology and Palaeontology,
Academia Sinica, Nanjing 210008, ChinaPresent address
Department of Earth System Science,Fukuoka University, Fukuoka 814-0180, Japan
Tetsuo SugiyamaDepartment of Earth System Science,
Fukuoka University, Fukuoka 814-0180, Japan
Katsumi UenoInstitute of Geoscience, University of Tsukuba,
Ibaraki 305-8571, Japan
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ANNOUNCEMENTS
International Conference on Pangea And ThePaleozoic-Mesozoic TransitionOrganizerProfessor Yin Hongfu, Member of Academia Sinica, President ofChina University of Geosciences (Wuhan)Objective The conference is designed to provide a forum to all kinds ofscientists who are interested in the special interval of Pangea fordiscussing Pangea formation and dispersion; global changes re-lated to Pangea integration and break-up; biotic crisis, extinction,recovery and evolution at the Paleozoic-Mesozoic transition; andTethys evolution during Pangea interval.DatePre-Conference Field Excursion: 7-8 March, 1999Conference: 9-11 March, 1999Post-Conference Field Excursion: 12-16 March, 1999PlaceChina University of Geoscience (Wuhan)LanguageEnglish will be the official language for all presentations.Important Dates1 April 1998: Deadline for submission of response to first circu-lar1 October 1998: Deadline for submission of abstracts1 February 1999: Deadline for submission ofpre-registrationThemes1. Tectonics and dynamics of Gondwana break-up, Pangea inte-gration and Tethys evolution;2. Paleogeography, paleoclimatology and paleoecology duringPangea interval;3. Stratigraphy, sea level changes, high-resolution events andboundary;4. Biotic crisis, mass extinction, recovery and evolution at thePaleozoic-Mesozoic transition.Field ExcursionPre-conference Field Excursion-Huangsi, Southeast Hubei Prov-ince (7-8 March, 1999). This two day field excursion will visitsome typical marine Carboniferous-Lower Triassic and terrestrialMiddle Triassic sections in Huangsi, southeastern Hubei Prov-ince. Some key boundaries will be examined there as well.Post-conference Field Excursion-the Yangtze Gorges (12-16March, 1999). The Yangtze Gorges areas are not only famous forthe attractive scenery and the Dam construction, but also for thewell-exposed Pre-Cambrian-Triassic stratigraphic sequences andtheir special geological significance. The excursion is plannedmainly to examine the stratigraphic sequence and it’s related geo-logical aspects. As the Yangtze Gorges Dam cut off the river at theend of 1997, a search for new exposures may be necessary.Publications We anticipate that refereed and accepted papers will be publishedeither as a book or as a special issue of an international journalseries. Papers must be presented (either orally or in poster) be-fore being considered for publication.
Registration and excursion Registration should be made on the registration form attached tothe second circular, which will be sent to all who respond to thefirst circular. Registration fee for the Conference (including theproceedings, morning and afternoon teas and three lunches) willbe $150 US Dollars. Pre-conference field excursion fee (includ-ing transportation, accommodation, field guidebook and meals)will be $120 US Dollars. As the Yangtze Gorges Dam is underconstruction and began daming the river late in 1997, the post-conference field excursion fee is presently uncertain but is esti-mated at about $500 US Dollars (refer to second circular for de-tails).Transportation Wuhan is the capital of Hubei Province, situated in the center ofChina. The international airport has daily flights from Hong Kong,Beijing, Shanghai, Guangzhou and other major cities in China.Wuhan is on the mid-way of Beijing-Guangzhou Railway withmore than 20 express and rapid trains daily from Beijing andGuangzhou. Meanwhile, Wuhan is situated in the middle part ofYangtze River with more than 10 scheduled boats from Shanghaiand Chongqing every day.Send all Correspondence to:Dr. Tong Jinnan (Secretariat)Faculty of Earth ScienceChina University of GeosciencesWuhan, Hubei 430074, P. R. CHINATel: +86-27-7482031 Fax: +86-27-7801763Email: [email protected]
XIV ICCP, First Circular XIV InternationalCongress On The Carboniferous And PermianHosted byThe Department of Geology and GeophysicsUniversity of Calgaryand University of Calgary Conference ServicesCalgary, AlbertaDateAugust 17-21, 1999Associated Meetings:The Pander SocietyThe Canadian Paleontology ConferenceSponsorshipThe Canadian Society of Petroleum Geologists has agreed to lendtheir nameas a supporting agency of this conference.Organizing CommitteeHonourary Chairman, Bernard MametChairman, Charles HendersonFieldtrips Chairman: Barry RichardsTechnical Program Committee:Charles Henderson, Bernard Mamet, Barry Richards, WayneBamber, Jim Barclay, Benoit Beauchamp, Richard Brandley,Pauline Chung, John Utting.Core Workshop Committee: Jim Barclay, Pauline Chung, Tony
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Hamblin.InvitationGeologists from around the world interested in Carboniferous andPermian rocks are invited to meet at Calgary Alberta Canada be-tween August 17-21, 1999.ThemeA World in Transition: Understanding Resources And Envi-ronment For TomorrowThe theme is intended to reflect a temporal duality. The worldtoday is in a state of transition from the industrial revolution to thecommunication -information revolution. Technological changesare occurring at an amazing pace, affecting the way we do ourscience. The world of the Carboniferous and Permian was also intransition as continental fragments amalgamated into Pangea andchanges occurred at a pace too great for many organisms. Thedeposition, burial, and alteration of communities of these organ-isms provided the resources for today. The integrative andmultidisciplinary efforts of current geoscientists to better under-stand the evolution of the earth during the Carboniferous and Per-mian will help us find more resources for tomorrow and provideinsight into important environmental questions about how we af-fect our world.Technical ProgramThe congress will focus on the many global aspects of Carbonif-erous and Permian environments and resources as well as the vari-ous system boundaries (Devonian/Carboniferous,mid-Carboniferous, Carboniferous/Permian, Permian/Triassic).The following are the major theme sessions planned:1. Carbiniferous-Permian conodonts; Pander2. Other conodonts; Pander3. Upper Paleozoic Palynology4. Other Paleontology (Forams, Corals, Brachs, Ammonoids)5. Mississippian Tectonics and Stratigraphy6. Pennsylvanian Tectonics and Stratigraphy7. Permian Tectonics and Stratigraphy8. Reefs9. Evaporites10. Phosphates11. Coal12. World Petroleum13. Boundaries/Chronostratigraphy14. Extinctions/Recovery15. Western Canada Carboniferous and Permian Geology; Petro-leum for Local crowd16. Canadian Paleontology; CPC17. General Sedimentology18. Global Synthesis; Climate, Cycles, Geochemistry, PangeaCore ConferenceThe Carboniferous of the Western Canada Sedimentary Basin con-tains substantial accumulations of conventional oil and gas (14%of basin’s conventional oil reserves and 16% of conventional gasreserves). The Permian contains about 2% of both conventionaloil and gas reserves of the eastern Canada Sedimentary Basin. Asa result there are many wells that have penetrated and cored theCarboniferous and Permian. The Core Research Centre of theAlberta Energy and Utilities Board is an outstanding facility inCalgary where most cores from wells in Western Canada are stored.A one day workshop during the Congress is planned.FieldtripsPre-convention trips (August 12-16, 1999)
Trip 1. Upper Carboniferous to Lower Permian paleoenvironmentsof the Maritimes Basin, Atlantic Canada. Principal leader J. Calder;start and end in Halifax Nova Scotia; 4 days duration.Trip 2. Mississippian tectonics and sedimentary facies; Idaho andMontana, USA. Principal leaders: P. Link and B. Skipp; trip willstart in Salt Lake City, USA and end in Calgary; 4 days duration.Trip 3. Structural geology of Canadian Rocky Mountain Foot-hills and FrontRanges west of Calgary. Principal leader M.E. McMechan; daytrip from Calgary.Trips 4 to 7. Carboniferous sequence stratigraphy, biostratigra-phy and basin development, Banff region of southwestern Alberta.This series of four day trips will provide an overview of the upperDevonian (Famennian) to upper Carboniferous (Moscovian) suc-cession along an east to west (shelf to deep basin) transect throughthe Rocky Mountain Foothills and Front Ranges near the towns ofBanff and Canmore. Excursions will leave from Calgary eachmorning and return in the evening. Participants can register forone or more of the trips, which will be run consecutively. Princi-pal Leaders: B.C. Richards, B.L. Mamet and E.W. Bamber.Trip 4. Lower Carboniferous (Tournaisian and Viséan) carbon-ates and clastics of the Moose Mountain oil and gas field, RockyMountain Foothills.Trip 5. Uppermost Devonian (Famennian) and Lower Carbonif-erous (Tournaisian) carbonates and black shale at Exshaw andMount Rundle, Rocky Mountain Front Ranges.Trip 6. Lower Carboniferous platform and ramp carbonates andUpper Carboniferous sandstones at Canmore and Banff, RockyMountain Front Ranges.Trip 7. Basin to supratidal carbonates, bedded chert and sand-stones in the thick Famennian to Permian section at Chester Lakein Kananaskis Country, western Rocky Mountain Front Ranges.Trip 8. Carboniferous cyclothems in the mid-continent region ofthe United States of America. Principal leader P. Heckle; trip willstart in Chicago, Illinois and end at Kansas City, Missouri; 5 daysduration.Post-convention trips (August 22-25)Trip 9. Sequence stratigraphy and biostratigraphy of Viséan toMoscovian carbonates and clastics in Rocky Mountain Foothillsand Front Ranges of Highwood Pass region, Alberta. Principalleaders B.L. Mamet, B.C. Richards and E.W. Bamber; day tripfrom Calgary.Trip 10. Pennsylvanian-Permian Oquirrh-Wood River Basin andPhosphoria Formation, eastern Idaho, USA. Principal leaders P.Link, B. Skipp; trip will start in Calgary and end at Salt LakeCity, Utah, USA; 4 days duration.Trip 11. Late Paleozoic Island arc and oceanic terranes,south-central British Columbia. Principal leaders J. Nelson, M.Orchard, T.W. Danner, and J.T. Fyles; trip will start in Calgaryand end at Kamloops, British Columbia; 4 days duration.Trip 12. Lower Carboniferous stratigraphy and basin develop-ment, Maritimes Basin, Atlantic Canada. Principal leaders P. Gilesand J Utting; trip will start and end in Halifax; 4 days duration.Trip 13. Structure and Lower Carboniferous stratigraphy of theRocky Mountain Front ranges southeast of Jasper, Alberta. Prin-cipal leader D. Lebel; trip will start and end in Calgary; 2 daysduration.Trip 14. Sequence stratigraphy and conodont biostratigraphy ofthe Upper Carboniferous and Permian in Rocky Mountain FrontRanges at Banff and Kananaskis Country, southwestern Alberta.
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Principal leaders C. Henderson and D. Moore; trip will start andend in Calgary; 2 days duration.Trip 15. Lower and Upper Carboniferous sequence stratigraphy,biostratigraphy and basin development on western margin of an-cestral North America in Cordillera of southwestern Alberta andsoutheastern British Columbia. Principal leaders B.L. Mamet, E.W.Bamber and B.C. Richards; trip will start and end at Calgary; 3days duration.Trip 16. Coal rich cyclothems in Kentucky. Don ChestnutMore details and accommodation forms will be sent to all whorespond to this notice or the first circular.Send All Correspondence to:XIV ICCPDepartment of Geology and GeophysicsUniversity of Calgary,Calgary, Alberta ,Canada T2N 1N4 orFAX: 403-284-0074 or email: [email protected]
International Field Conference on: The continentalPermian of the Southern Alps and Sardinia (Italy).Regional reports and general correlations.Date: 16-25 September, 1999VenueBrescia Museum of Natural Sciences, Italy, and excursions inSardinia and in the Southern Alps.OrganizerA team of Italian geologists already involved in the IGCP projectsn. 203, 272, 343, 359, jointly sponsored by the Italian GeologicalSociety (SGI), the National Research Council (CNR), and otherscientific organizations. Foreign geologists have also collabo-rated for this meeting.SubjectsThe proposed aim of the Conference is not only to present theresults of research carried out over recent years in the aforemen-tioned Italian areas, but above all, to establish possible correla-tions between these regions and other Permian continental do-mains of the world. Two field trips are planned. The first pre-Conference excursion will be held, from 16 to 18 September, inSardinia, specifically both in the central-eastern continental ba-sins of Escalaplano, Perdasdefogu, Seui, and in the northwesternNurra. Afterwards, the participants can reach Brescia by ferry-boat and bus. The Conference, which will take place in Bresciafrom 20 to 22 September, is designed to improve our current un-derstanding of the continental Permian; as well as the presenta-tion of papers and posters, there will be restricted meetings onspecific research topics. The focus will be on stratigraphic,palaeontologic, magmatic and tectonic separate sections. An ad-ditional section on the Permian-Triassic boundary in the conti-nental, or on the continental-marine transition domains, is beingplanned. A further three-day excursion, from 23 to 25 September,will be dedicated to the Permian of the central-eastern SouthernAlps. The Collio and Tregiovo continental basins, the Bolzanovolcanics, and the Val Gardena Sandstone-Bellerophon Forma-tion of the well-known Butterloch-Bletterbach section in the west-ern Dolormites, will all be visited. The trip will also take in thefamous P/T type-section of Tesero, near Cavalese (Fiemme Valley).
CorrespondentProf. G. Cassinis, Dipartimento di Scienze della Terra, Universitadi Pavia, Via Ferrata 1, I-27100 Pavia, Italy- Phone. 39-382-505834, telefax: 39-382-505890, Email: [email protected]
31st International Geological CongressThe International Commission on Stratigraphy andSubcommission on Permian Stratigraphy will spon-sor a international symposium on:International Standard References for the PermianSystem: Cisuralian of Southern Ural Mountains,Guadalupian of Southwestern North America,Lopingian of South China
Date: August 6th through 17th, 2000Venue: Riocentro Convention Center Rio de Janeiro - BrazilSubject: The symposium is to showcase progress on final recom-mendations for Permian series and stage definitions. This sympo-sium creates the forum for the working groups of the SPS to presenttheir findings and conduct an open discussion on the PermianSystem. The symposium will consist of both an oral and a postersession held during the scientific program of the 31st InternationalGeological Congress. This is a general announcement, detailswill be given in subsequent issues.
Conveners: Brian F. Glenister (University of Iowa), Bruce R.Wardlaw (USGS), Tamra A. Schiappa (BSU)
Correspondent: Tamra A. Schiappa, Permian Research Institute,Boise State University, Boise, Idaho, 83725, USA. Email:[email protected].
